Growth characteristics of apple cultivar grafted onto the transformed M26 with rolA rolB genes

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为什么苹果很迷人（Whyisappleattractive）

为什么苹果很迷人（Why is apple attractive）Why Apple is very charming? Why Apple fans are crazy to follow? One of the top products charm is reflected in what areas? Is the product itself or the brand itself has the taste, elegant, noble, fashion and other elements, which is not only the use value is the product brand personality.In this era of brand success, we should stand out in many excellent brands, and only rely on functional characteristics. We should give more humanistic factors to the brand to make it more attractive. Apple's market capitalization exceeds Microsoft's $about 100000000000, equivalent to more than a HP. Over the past 10 years, the PC industry has undergone an earthshaking change, not by technology started, apple basically looking for the right direction, from PC to consumer electronics products, to the Internet, and then to the mobile internet. Jobs is not technology oriented, that is, by leading a certain technology to dominate the mobile internet. His success is more likely to be customer oriented, based on understanding human nature, controlling human desires, and demanding detail. Thus all the way to achieve the acme of human marketing.No marketing, first campaignOften the more unknown things are coming, the more people are eager to know the truth. And enterprises use good people this kind of onlookers and watching the mood, can let you use low cost, also can do propaganda.As Drucker, the managing guru, said, "the goal of marketing isto make selling unnecessary." this is the real marketing realm, and Apple really does. More than a year after Apple fans were looking forward to Apple's mobile phone, online discussions continued, and some even claimed to have gotten a design for the iphone. But until that day released, people finally see the true face of the iPhone, almost everyone guessed it called iPhone, but almost everyone did not guess his style, his performance even more amazing. Just as love is truly gratifying, not the process of marriage, but the pursuit of it. Mystery of consumer psychology and explore the unknown results of worry about personal gains and losses, is the most valuable product promotion and brand promotion marketing tool.In a world awash with commercial propaganda, the goal of creating momentum is to make sure that marketing products are the subject of conversation. The Apple Corp will market its products as a sign of the times meaning of the items, the advanced technology innovation to boast as if it were raining flowers for customers eager to get intoxicated, but in the end, you will find that your home is to buy a mobile phone or a "smart" mobile phone.Hunger marketingApple products are so popular, largely from the control of the market supply, which is the market in a relatively "hungry", which helps maintain the stability of the price of their products and the control of the product upgrade. IPhone's sales are clearly a proxy for this strategy.Since the listing, no matter how high the market for thisproduct, Apple Corp has always insisted on limited supply. A lot of people might want to buy one because they can't buy it. Someone even gets what he does not know at a great cost, and he is content with the joy he has, and sometimes he is not sure what he wants,And Apple's hunger marketing is just the use of people in the fashion, chasing fashion mentality.Apple and Jobs are arrogant and powerful. Many consumers lined up all night long for products such as "buy a product" and "lift up" people's appetites without rushing to meet them. Do not meet attracted more attention, which is why more than a limited edition of people chasing you. Apple's marketing attitude is also strengthening its product style: strong, arrogant and maverick. Because it is not easy to own, it will be more precious, more different. This strong marketing style and its products, people love to hate, unable to stop.Experiential Marketing - let users suffer different mysterious feelingsJobs always think about this problem, namely the user experience of the product is? Each Apple Corp launched a new product promotion, will choose the theater is full of mystery, to promote products through the drama form, aroused curiosity.How to make the user experience, the first step is to demonstrate. Neuroscientists have found that the brain is easily bored. Jobs won't let you have time to lose interest. He usually spends only 10 minutes showing a new product or newfeature, and it's a lot of fun. When Jobs launched iPhone at the Macworld conference, he showed how Google maps were used on iPhone. Jobs checked the local Starbucks store list through iPhone and said, "let's give it a try."". So he dialed the phone, and Jobs, speaking to the audience, said to the other end of the line, "I want to order 4000 cups of latte.". No, it's just a joke". It's just a joke, but everyone in front of the TV screen wants to buy an impulse to experience it.At the same time, Jobs has incendiarypower very strong, he has a legendary story, unconventional life, and people love hate henzhao. This is Jobs's unique charm of personality charm. Think about how Jobs persuaded PepsiCo President John Sculley to join apple in 1983: "do you want to sell sugar all your life, or change the world?"Build Apple culture and train crazy apple fans. Apple computer has a distinctive mark in the minds of consumers, that is: excellent performance, made the appearance and perfect design, apple computer means unique, means "industrial design Cool", means of fashion. Jobs tries to make every product conform to the consumer's understanding of apple culture. And Apple's every one can make consumers happy to say: "this is my apple! Coca-Cola in the beverage industry occupies the first place in consumer psychology, and therefore represents the value of the United States.". Jobs has also made apple the first place in innovative and creative culture, with a starting point different from that of other brands.As a matter of fact, customers do not want to be flattered. Sometimes, if they try to please them, they may not know whatto do. It is better to arouse their interest by hanging their appetites. Modern marketing advocates: "as long as the customer needs, how much?"." And human marketing is deliberately control the supply, not to make it easy for customers to meet: "do you want? No goods, try again next time."." Many apple products will have a lot of shortages before and after their launch.This caused the market hunger approach, but it uses a. Those who identify with my values are my consumers. Follow me, please. Apple's marketing has used the brand spirit and value to call and guide consumers, beyond the pure product level, this is the brand marketing pursuit of the highest realm.The word of mouth marketing -- let the mobile phone into the era of toys from communication toolsMarketing process must make people feel happy and arouse the interest of others, so that some people volunteer to participate. At the moment of the normalization of the Internet micro-blog (MicroBlog), the iPhone mobile phone acts as a fashion tool for the entertainment public. Micro-blog's ultra high popularity entrepreneurs, stars are using iPhone sent a variety of information, information below will also mark this information from iPhone users. This allows more people to play with micro-blog want to have this logo.Which cell phone brand is being chased like a star? Probably only apples. "Apple fans chasing apple, often selfless people around to dazzle their love machine, personally demonstrate, using exchange ideas, show personality love machine parts, even wherever holding an apple laptop. Even SONY, DELL, NOKIA thesefamous first-class brand, its users can not with enthusiasm "apple" crazy compared.The extreme nature of marketingWhy are apples so attractive? In front of Apple Corp, allso-called star products will be eclipsed. Any Apple released a new product, can make the world Apple fans for their products and crazy, media is widely reported but also affect the stock market fall over each other, and affect the industry, this is the nature of marketing Apple Corp.Jobs's philosophy is "doing the right thing". This is correct, not technology, design, aesthetics, but human nature". In fact, at that time, Jobs's eyes "the right thing" is contrary to tradition. For example, iPhone has infrared sensing function, automatically close the screen when you call. When you call iPhone on your face, iPhone automatically closes the screen to save power. This is not much of a smart technology, why are many people focused on the company did not find?. NOKIA also has a distinctive brand personality, that is cost-effective, durable, but this character can only be attributed to physical property. Rather than selling products, apple is selling humanity, products to consumers, the "like-minded" people together.In 1994 Jobs Macintosh computer (Macintosh, Mac) was born 10 years when a confession, as his "ultimate rule of human nature understanding": "go deep into the core of the problem, we can understand its complexity, but also to find out the fundamental solution. Most people do this and they usually stop. But really great people will continue to explore, and finally can find thehidden problems behind the crux of the problem, and then provide a beautiful and elegant solution. That's our ambition to design the macintosh."There is a country with two a good carpenter, one day the king out of the question to let them decide the outcome to. Ask two carpenters to carve a mouse to see who carved it. The first carpenter's mouse was so lifelike that it filled the king with praise.The second carpenters did nothing but a mouse, without the shape of a mouse. When the king was about to announce that the first carpenter had won, the second carpenters refused to say, "I'm looking for a cat to see who's more like.". When looking for a cat, the cat pounced on the second mouse without hesitation. So the "first" of the title to the second carpenter, the king asked him, what can let the cat think his more mouse like? He replied, I used the fish bone in mice.In fact, life is much less so. Those who are successful are not necessarily the best people who can do it. Often the person who knows best about the needs of the cat. The ultimate goal of an enterprise is to meet customer needs. Only the mentality of the cat, the cat (customer) perspective to observe what kind of mouse (product) is its favorite, the cat's behavior to marketing this "rat."". In order to let customers first time like this "rat"". This is the essence of human marketing, and Jobs is the marketing of human nature to the extreme.。

苹果栽培中的遗传工程：机遇与挑战英语作文

Genetic engineering in apple cultivation presents both opportunities and challenges. By modifying the genetic makeup of apple trees, scientists can create varieties that are more resistant to diseases, pests, and environmental stress, leading to increased yields and improved quality. This can potentially help address issues such as food security and sustainability.One of the key opportunities of genetic engineering in apple cultivation is the development of disease-resistant varieties. By introducing genes that confer resistance to common apple diseases such as apple scab and fire blight, scientists can reduce the reliance on chemical pesticides, thus promoting environmentally friendly and sustainable agricultural practices.Furthermore, genetic engineering can also be used to enhance the nutritional content of apples, such as increasing their antioxidant levels or improving their storage and shelf life. This could lead to the development of apple varieties that are not only healthier but also more accessible to consumers.However, the use of genetic engineering in apple cultivation also comes with challenges. One of the major concerns is the potential impact on biodiversity and natural ecosystems. Introducing genetically modified (GM) apple varieties into the environment may have unintended consequences, such as the spread of modified genes to wild apple populations or the disruption of ecological balance.Moreover, consumer acceptance and regulatory approval of GM apples remain significant hurdles. Many consumers are wary of genetically modified foods, and there is a need for transparent communication and education to build trust and acceptance. Regulatory frameworks also need to be established to ensure the safety and ethical use of genetically modified apple varieties.In conclusion, genetic engineering in apple cultivation offers promising opportunities for improving crop resilience, quality, and nutritional value. However, it also presents challenges related to environmental impacts, consumer acceptance, and regulatory oversight. Addressing thesechallenges will be crucial to realizing the full potential of genetic engineering in apple cultivation.。

苹果的几个种的介绍英文版

Granny Smith
A start, green apple originating from Australia It solid flush and tangy flatter make it ideal for cooking and bagging, as well as for fresh eating
by free radials Additionally, the fiber in green apples can aid in digestion and weight loss
04
Apple type three: yellow apples
The characteristics of yellow apples
The Origin and Distribution of Yellow Apples
Origin
Yellow apples originated in Central Asia, where they have been cultivated for those of years They were later introduced to Europe and North America by traders and explorers
Overview of Apple Varieties
Red Delicious
One of the most popular apples worldwide, known for its bright red color, sweet taste, and firm texture After used for fresh eating and in bagging
patches of yellow or green

评估种植密度对苹果园产量的影响英语作文

Assessing the impact of planting density on apple orchard yield is crucial for optimizing agricultural productivity. Different planting densities can have varying effects on the amount and quality of apples produced.Planting at higher densities can result in increased competition for resources such as sunlight, water, and nutrients among the apple trees. This may lead to smaller individual tree size, but the overall yield per unit area could potentially increase due to more trees being planted. However, if the density is too high, it might lead to overcrowding and reduced air circulation, which could increase the risk of disease and pest infestations.Conversely, lower planting densities allow for more space between trees, reducing competition for resources and potentially leading to larger individual tree size and increased fruit size. However, this may also result in lower overall yield per unit area due to fewer trees being planted.Finding the optimal planting density involves a careful balance between maximizing individual tree growth and overall yield. Factors such as apple variety, soil fertility, climate, and management practices all play a role in determining the ideal planting density for a specific orchard.Conducting field trials and experiments with different planting densities can provide valuable data to evaluate their impact on apple orchard yield. By carefully monitoring factors such as tree growth, fruit production, and fruit quality, researchers and growers can determine the most suitable planting density for their specific conditions.In conclusion, the impact of planting density on apple orchard yield is multi-faceted and requires careful evaluation. Finding the optimal balance between tree size, resource competition, and overall yield is essential for maximizing productivity in apple orchards.。

种苹果的英语作文怎么写

Growing up in a small rural town, I was surrounded by the lush greenery of apple orchards that stretched as far as the eye could see. The scent of fresh apples filled the air, and the sight of the vibrant red and green fruits hanging from the trees was a sight to behold. This was the world I was born into, and it was the world that shaped my childhood and my love for the simple yet rewarding process of growing apples.My family owned a modest apple orchard, and from a young age, I was involved in the cultivation process. The first step in growing apples is selecting the right variety of apple trees. There are countless varieties, each with its unique characteristics, such as size, taste, and resistance to diseases. My father, being an experienced farmer, taught me the importance of choosing trees that would thrive in our local climate and soil conditions.Once the trees were selected, the next step was planting. This involved digging holes deep enough to accommodate the root system of the saplings, and then carefully placing them in the ground. The process required patience and precision, as the trees needed to be positioned at the right angle and depth to ensure their healthy growth.As the trees began to grow, we had to ensure they received adequate water and nutrients. This involved regular watering, especially during the dry seasons, and applying organic fertilizers to enrich the soil. The process was laborintensive, but it was also deeply satisfying to see the trees flourish under our care.Pruning was another crucial aspect of apple cultivation. This involved trimming the branches to promote healthy growth and to ensure the trees received enough sunlight. It was a delicate process that required a keen eye for detail and an understanding of the trees growth patterns.One of the most exciting parts of growing apples was the harvest season. The sight of the trees laden with ripe, juicy apples was a testament to the hard work and dedication that went into their cultivation. The process of picking the apples was a family affair, with everyone involved in the careful selection and collection of the fruits.However, growing apples was not without its challenges. Pests and diseases were a constant threat, and we had to be vigilant in monitoring the health of the trees. This involved regular inspections and the use of organic pest control methods to ensure the quality and safety of our apples.Despite the challenges, the joy of growing apples far outweighed the difficulties. There was something incredibly rewarding about seeing a tiny sapling transform into a robust tree bearing delicious, healthy fruits. It was a testament to the power of nature and the impact of human care and attention.Moreover, growing apples taught me valuable life lessons. It taught me about patience, as the process of growing apples takes time and cannot be rushed. It taught me about resilience, as we had to adapt to changing weather conditions and overcome setbacks. And most importantly, ittaught me about the satisfaction that comes from nurturing something and watching it grow.In conclusion, growing apples is more than just a hobby or a profession its a deeply fulfilling experience that connects us with nature and teaches us valuable life lessons. Its a process that requires dedication, patience, and care, but the rewards are well worth the effort. Whether youre a seasoned farmer or a novice gardener, the joy of growing apples is a universal experience that brings people closer to the earth and to each other.。

苹果果实的生长过程作文

苹果果实的生长过程作文英文回答：The growth process of an apple fruit is a fascinating journey. It all starts with a tiny apple blossom, which blooms on the apple tree during the spring season. The blossom is pollinated by bees or other insects, and this is a crucial step in the fruit's development.After pollination, the apple blossom starts to wither and fall off, making way for the tiny apple fruit to form. At this stage, the fruit is still very small and green. It takes time for the apple to grow and ripen into a juicy and delicious fruit.As the apple continues to grow, it absorbs nutrients from the soil through its roots and receives sunlight through its leaves. These essential elements provide the energy for the apple to develop and mature.During the growth process, the apple undergoes various changes. Its color changes from green to yellow, red, or a combination of both, depending on the apple variety. The texture of the fruit also becomes smoother and the flavor becomes sweeter.Finally, when the apple is fully grown and ripe, it is ready to be harvested. Farmers carefully pick the apples from the trees, making sure to handle them with care to avoid any damage. The harvested apples are then sorted, packed, and transported to markets or grocery stores for people to enjoy.中文回答：苹果果实的生长过程是一个迷人的旅程。

他教我怎样种苹果英语作文

Growing up in a small rural town, I was always surrounded by the lush greenery of apple orchards that dotted the landscape. The sight of those vibrant trees laden with fruit was not just a feast for the eyes but also a source of livelihood for many families in our community. It was in this setting that I learned a valuable life lesson from an unexpected mentorMr. Thompson, the old apple farmer.Mr. Thompson was a man of few words but many actions. His hands, rough and calloused from years of labor, spoke volumes about his dedication to his craft. One summer, when I was about 15, I found myself at a crossroads, unsure of what to do with my free time. It was then that Mr. Thompson offered me a chance to learn something practical and rewardinghow to grow apples.The first lesson was about understanding the apple tree itself. Mr. Thompson explained that each variety of apple has its own set of needs and characteristics. He showed me how to identify the different types of trees by their leaves, bark, and the shape of their branches. It was fascinating to learn that the same species could have such diverse appearances.Next, he taught me the importance of soil preparation. Good soil is the foundation of a healthy tree, he would say. We spent hours turning the soil, enriching it with compost, and ensuring proper drainage. I learned about the pH levels and how they affect the nutrients available to the tree. This was no easy task, but the satisfaction of seeing the soil come to life was immeasurable.As the season progressed, Mr. Thompson introduced me to the art of pruning. With a sharp pair of shears in hand, he demonstrated how to remove dead or diseased branches, encouraging new growth and shaping the tree for better fruit production. It was a delicate balance between cutting back and allowing the tree to flourish.Watering was another crucial aspect of apple farming that I learned to appreciate. Mr. Thompson emphasized the importance of regular, deep watering to encourage strong root systems. He showed me how to check the soils moisture levels and when to adjust the watering schedule based on weather conditions.But perhaps the most rewarding part of the process was the actual planting of the apple seeds. Mr. Thompson taught me how to stratify the seeds, a process that mimics the natural winter cold required for germination. We then planted them in rows, covering them with a thin layer of soil, and I eagerly awaited the emergence of tiny green shoots.Throughout the summer, I watched as the trees grew, their branches heavy with the promise of a bountiful harvest. Mr. Thompson taught me about the pests and diseases that can affect apple trees and how to manage them organically. He showed me how to use natural predators and homemade sprays to keep the orchard healthy.As the season drew to a close, the time came to harvest the apples. It was a joyous occasion, filled with laughter and the sweet scent of ripe fruit. Mr.Thompson taught me how to pick the apples gently, ensuring not to bruise them, and how to store them properly to extend their freshness.What started as a simple summer activity turned into a profound learning experience. Mr. Thompsons teachings went beyond the practical skills of apple farming they instilled in me a deep appreciation for natures cycles and the hard work that goes into producing the food we enjoy.Years have passed since those summer days in the orchard, but the lessons I learned from Mr. Thompson continue to resonate with me. They have shaped my understanding of responsibility, patience, and the interconnectedness of life. And every time I bite into a crisp, juicy apple, I am reminded of the wisdom of that humble farmer who taught me not just how to grow apples, but how to appreciate the beauty and complexity of life itself.。

苹果对未来的影响英语作文

苹果对未来的影响英语作文The Impact of Apple on the Future。

Apple Inc. is a technology company that has revolutionized the way we live our lives. Since its founding in 1976, the company has been at the forefront of innovation, producing products that have changed the way we communicate, work, and play. From the Macintosh to the iPhone, Apple has consistently pushed the boundaries of what is possible, and its impact on the future is undeniable.One of the most significant ways that Apple has influenced the future is through its products. The Macintosh computer, which was introduced in 1984, was one of the first computers to have a graphical user interface, making it much easier for people to use. This innovation paved the way for the modern computer, which is now an essential tool in almost every industry.The iPod, which was introduced in 2001, was another game-changer. It was the first portable music player that allowed people to carry thousands of songs with them wherever they went. This innovation transformed the music industry, making it easier for people to discover andlisten to new music.The iPhone, which was introduced in 2007, was perhaps the most significant product in Apple's history. It was the first smartphone that combined a touch screen with a powerful computer, allowing people to do everything from browsing the web to taking high-quality photos. The iPhone has since become an essential tool for millions of people around the world, and it has spawned an entire industry of app developers and accessory makers.Another way that Apple has influenced the future is through its focus on design. Apple products are known for their sleek, minimalist design, which has become a hallmark of the company. This focus on design has inspired other companies to prioritize aesthetics in their products, leading to a more visually appealing and user-friendlyworld.Apple has also had a significant impact on the economy. The company is one of the largest in the world, with a market capitalization of over $2 trillion. Its success has created thousands of jobs and has spurred innovation inother industries. Apple's supply chain, which spans the globe, has created opportunities for businesses incountries like China and Taiwan.Finally, Apple has influenced the future through its commitment to sustainability. The company has set ambitious goals for reducing its carbon footprint and has made significant progress in areas like renewable energy and recycling. Apple's commitment to sustainability hasinspired other companies to take similar steps, leading toa more environmentally friendly world.In conclusion, Apple has had a profound impact on the future. Its products have transformed the way we live, work, and communicate, and its focus on design has inspired other companies to prioritize aesthetics. Apple's success hasalso had a significant impact on the economy, and its commitment to sustainability has helped to create a more environmentally friendly world. As Apple continues to innovate and push the boundaries of what is possible, its impact on the future is sure to be even greater.。

苹果的生长过程的英语作文

苹果的生长过程的英语作文The journey of an apple from a tiny seed to a succulent fruit is a fascinating tale of nature's wonders. This essay delves into the stages of apple growth, from germination to harvest.GerminationThe life of an apple begins with a seed, which, when planted in nutrient-rich soil, starts the process of germination. The seed absorbs water, and its outer shell, or seed coat, softens, allowing the embryonic root to emerge. This initial stage is critical as it sets the foundation for the apple tree's development.Seedling StageAs the seedling emerges above the soil, it develops its first set of leaves, known as cotyledons. These leaves aredifferent from the mature leaves and are responsible for the early photosynthesis, providing energy for the young plant's growth.JuvenilityThe juvenile phase is characterized by rapid growth and the development of a more complex root system. During this time, the tree establishes itself, and its leaves become more mature, transitioning from simple to compound structures.Vegetative StageThe vegetative stage is marked by the tree's focus on developing a strong structure. It forms branches and a more extensive root system, preparing for the energy-intensive process of flowering and fruiting.FloweringApple trees are known for their beautiful blossoms. The transition from vegetative to reproductive growth is signaled by the appearance of flower buds. When the conditions are right, these buds open to reveal delicate, often white or pink flowers, which are pollinated by bees and other insects.Fruit SetPollination leads to the formation of tiny apples, or fruits. The tree's energy shifts from growth to nurturing these developing fruits. The young apples, or fruits, are initially small and green, protected by a papery husk known as the calyx.Cell ExpansionAs the apple grows, cells expand, and the fruit increases in size. This is the stage where the apple's final size and shape are determined. The fruit's skin becomes smoother, and the color begins to change from green to a more mature hue.MaturationDuring maturation, the apple's sugars increase, and thefruit's color deepens. This is the stage where the apple develops its characteristic sweetness and tartness. Thefruit's skin becomes firm and glossy, signaling that it is nearing full ripeness.HarvestThe final stage is the harvest. Apples are typically picked once they have reached their peak in terms of color, size, and taste. Harvesting is done by hand or with the aid of mechanical devices to ensure the fruit is not bruised or damaged.Post-HarvestAfter being harvested, apples can be stored for extended periods, allowing them to be enjoyed throughout the year. The storage conditions are carefully controlled to maintain the quality and freshness of the apples.In conclusion, the growth process of apples is a testament to the cycle of life and the interplay of nature's elements. From a tiny seed to a fruit enjoyed worldwide, the appletree's journey is a remarkable one, filled with biological intricacies and agricultural artistry.。

有关苹果的英语作文

The Apple:A Fruit of Legend,Science,and HealthThe apple,with its crisp bite and sweet aroma,stands as one of the most iconic fruits in human history.Its journey from the wild forests of Central Asia to the global staple it is today is a tale interwoven with mythology, agriculture,and science.Revered in ancient cultures,studied by scientists,and loved by millions,the apple holds a place in our world that transcends mere nutrition.This essay explores the multifaceted nature of the apple,its historical significance,varieties,health benefits, and its role in culture and science.Historical SignificanceThe apple's story begins in the Tien Shan mountains of Kazakhstan, where its wild ancestor,Malus sieversii,still grows.These ancient apples were far from the sweet,cultivated varieties we enjoy today,but they laid the foundation for a fruit that would captivate the world.Apples spread along the Silk Road,with each civilization that encountered them—from the Greeks to the Romans—cultivating and cherishing the fruit.In Norse mythology,apples were believed to grant eternal youthfulness,a theme echoed in the biblical story of Adam and Eve, where the apple symbolizes knowledge and temptation.Varieties and CultivationToday,there are over7,500varieties of apples grown around the globe, each with its unique flavor,color,and texture.From the tart Granny Smith to the sweet Fuji,the diversity of apples available is a testament to centuries of cultivation and breeding.The development of these varieties has been driven by both natural adaptation and human selection,with modern horticulturists continuing to breed apples for qualities like disease resistance,yield,and taste.Health BenefitsBeyond their cultural and historical significance,apples are a powerhouse of nutrition.Rich in fiber,vitamins,and antioxidants,apples have been linked to numerous health benefits.Studies suggest that eating apples can improve heart health,reduce the risk of diabetes,and aid in weight management.The old adage"an apple a day keeps thedoctor away"holds a kernel of truth,as the regular consumption of apples contributes to overall health and well-being.Apples in Culture and ScienceThe apple has also made its mark in culture and science.The story of Isaac Newton's discovery of gravity is perhaps the most famous apple-related legend,where an apple falling from a tree prompted him to ponder the forces at play.In art and literature,apples appear as symbols of beauty,sin,and knowledge.Scientifically,apples have been at the heart of genetic research,with the sequencing of the apple genome providing insights into fruit development,ripening,and the history of domestication.ConclusionThe apple,in its simple,round form,encompasses a world of history, culture,and science.It reminds us of humanity's journey from nomadic tribes to settled agriculturists,of myths that sought to explain the natural world,and of the ongoing quest for knowledge and health.As we enjoy an apple,crisp and fresh,we partake in a legacy that spans thousands of years and reflects the interconnectedness of our world. The apple,thus,is more than just a fruit;it is a symbol of human curiosity,a bearer of health,and a bridge between the past and the present.。

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Plant Science147(1999)75–80Growth characteristics of apple cultivar Gravenstein plants grafted onto the transformed rootstock M26with rol A and rol B genes under non-limiting nutrient conditionsLi-Hua Zhu*,Margareta WelanderDepartment of Horticulture,The Swedish Uni6ersity of Agricultural Sciences,Box55,S-23053Alnarp,SwedenReceived14December1998;received in revised form28May1999;accepted28May1999AbstractThe growth characteristics of the apple cultivar(Malus domestica)Gravenstein(GR)grafted onto the transformed rootstock M26were investigated.The transformed rootstocks used in the experiments included two clones with the rol A gene(rol A1and rol A2)and one clone with the rol B gene(rol B).The grafted plants consisted of GR/rol A1,GR/rol A2and GR/rol B and the control plants GR/M26(the untransformed rootstock).Ingestad’s experimental system was employed for growing the plants to maintain non-limiting nutrient conditions and to achieve accurate and comparable results.The results show that the grafted GR/rol A1,GR/rol A2,and GR/rol B plants had a similar relative growth rate to the GR/M26plants,indicating no effect of the transformed rootstock on relative growth rate under non-limiting nutrient conditions.Moreover,the transformed rootstocks inﬂuenced neither the leaf area ratio,speciﬁc leaf area values nor dry matter allocation.However,the GR/rol A1plants did show a reduced stem length and a decreased internode length compared to the control and the other two transgenic clones.Also,the GR/rol A1and GR/rol A2showed a signiﬁcant lower speciﬁc root length value compared to the control.The present results suggest that the dwarﬁng effect does not relate to the relative growth rate of the rootstock.The transformed clone rol A1and rol A2,especially rol A1,might be potential dwarﬁng rootstocks for apple production.©1999Elsevier Science Ireland Ltd.All rights reserved.Keywords:Apple;Rootstock M26;rol Gene;Steady-state;Dwarﬁng;Relative growth rate/locate/plantsci1.IntroductionDwarﬁng rootstocks have been used world-widefor commercial apple production.The importanteffects of dwarﬁng rootstocks are tree size reduc-tion,early bearing and high yield efﬁciency[1–3].Although a number of dwarﬁng and semi-dwarﬁng apple rootstocks are available,there areno ideal dwarﬁng rootstocks for commercial pro-duction.For example,some dwarﬁng rootstocksare difﬁcult to root and have a bad tree anchoragewhich needs expensive staking[3,4].Some semi-dwarﬁng rootstocks are not dwarf enough.Thecommercially important rootstocks thus need tobe improved.Genetic improvement of apple rootstocks bytraditional breeding and selection methods is avery slow process due to the long life cycles.However,by applying genetic engineering,the im-provement of apple rootstocks can be speeded upgreatly[5–8].Another advantage of genetic engi-neering over conventional breeding methods isthat the recipient plant gains only the gene ofinterest while the genetic framework of the recipi-ent plants remain unchanged.Wild Agrobacterium rhizogenes in nature con-tains three T-DNA gene loci,named rol A,rol Band rol C which are responsible for the changes ofgrowth characteristics in the infected plants[9].The rol A gene has been proved to be associated *Corresponding author.Tel.:+46-40-41-53-73;fax:+46-40-46-04-42.E-mail address:li-hua.zhu@tv.slu.se(L.-H.Zhu)0168-9452/99/$-see front matter©1999Elsevier Science Ireland Ltd.All rights reserved.PII:S0168-9452(99)00102-8L.-H.Zhu,M.Welander/Plant Science147(1999)75–80 76with shortened internodes of transgenic plants ex-pressing the rol A gene,while the rol B and rol C genes are suitable for improving the rooting ability and root architecture[10–12].It is of great interest for commercial apple production to introduce the rol B and rol C genes to difﬁcult-to-root rootstocks and to introduce the rol A gene to vigorous root-stocks to improve rooting ability and to further dwarf trees.M26is a semi-dwarf apple rootstock.Although it has a relatively good rooting ability and a semi-dwarf character,the rooting percentage with-out auxin(IBA)treatment for conventional cut-tings is low and it is not dwarf enough in some apple production areas.It is still of a commercial interest to increase the rooting ability and to dwarf it.For this purpose,we have transformed M26with the rol A and rol B genes separately conferring a dwarfer phenotype and an increased rooting ability via Agrobacterium-mediated gene transfer[5,6].However,how these transgenic root-stocks will inﬂuence growth characteristics of the cultivar grafted onto them needs careful evalua-tion before any commercialisation.The aim of this study was to investigate the effect of the transgenic M26rootstocks on growth characteristics of the apple cultivar Gravenstein grafted onto them un-der non-limiting nutrient supply conditions.2.Materials and methods2.1.Plant materialsIn vitro grafted apple(Malus domestica)plants were used in this study.The scion was the cultivar Gravenstein(GR)and the rootstocks were the untransformed M26(M26),two transformed clones of M26with the rol A gene(rol A1and rol A2)and one clone with the rol B gene(rol B). The four grafted combinations used in the experi-ments were GR/M26,GR/rol A1,GR/rol A2and GR/rol B.We have chosen one rol B clone and two rol A clones for the experiments based on the following reasons:originally,two rol B trans-formed clones and four rol A transformed clones of M26were obtained.For the rol B clones,we had chosen the one which rooted better in vitro and without the GUS gene because of its better rooting ability and because of no GUS gene in-volved.In vitro cultures show that the clone with the GUS gene has not been growing as normally as the one without the GUS gene,so we did not include that clone to avoid the possible negative effect of the GUS gene on growth in future com-mercial use.For the rol A transgenic clones,to facilitate the aim of our study,we chose the two dwarfer ones among the four transgenic clones based on greenhouse experiments[5].2.2.RootingFor the untransformed M26,the shoots were rooted in rooting medium containing Quoirin and Lepoivre’s macro and micro elements[13], Walkey’s vitamins[14]supplemented with0.25mg/ l IBA,30g/l sucrose(pH5.5)and solidiﬁed with6 g/l agar in the dark for4days,then transferred to IBA-free rooting medium in the light.For the rol B shoots,rooting was done in the same rooting medium but without IBA,while the rol A shoots were rooted in the same rooting medium with 0.125mg/l IBA in the dark for4days,then trans-ferred to IBA-free rooting medium in the light.All shoots were grown in a controlled climate cham-ber at a temperature of23/18°C(day/night),a light intensity of33m mol/m2/s(PAR)(cool-white ﬂuorescent light,38W,Phillips,Holland)and a photoperiod of16h.2.3.GraftingIn vitro grafting was performed according to the procedure described by Drs C.Monney and G. Douglas(personal communication).Similar stem diameters of the rooted rootstocks and the un-rooted scions were selected and a diagonal cut as long as possible was made across each.The stem of the rootstock was inserted into a sterilised silicone tube from one end and the stem of the scion from the other.The two parts were pushed together to form a tight union and the new plants were placed in the rooting medium as described above supplemented with0.125mg/l IBA and solidiﬁed with4g/l agar and placed in a controlled climate chamber as above for about50days. When the new leaves appeared the plants were ready for growth experiments.L.-H.Zhu,M.Welander/Plant Science147(1999)75–80772.4.Growth experimentsThe plants were grown in growth units with a closed root compartment,in which the culture solution containing the nutrients was sprayed con-tinuously onto the roots as described by Ingestad and Lund[15,16].The nutrients were frequently added to the culture solution by pH titration based on the relative addition rate which equals the relative uptake rate and equals the relative growth rate of plants growing under steady-state conditions.The nutrient proportions were 100:13:65:7:8.5for N,P,K,Ca and Mg on a weight basis with nitrate as the sole nitrogen source.The growth units were placed in a con-trolled environmental chamber at a temperature of 18°C,a relative humidity of70%,a light intensity (PAR)of200–210m mol/m2/s(cool-whiteﬂuores-cent tubes,215W,Sylvania,Canada)and a pho-toperiod of18h.For each time a single experiment was conducted in one growth unit. Every experiment lasted for about30–60days, depending on relative growth rate(g/g/day).All the experiments were conducted under non-limit-ing nutrient conditions,i.e.all nutrients were available to the plants.Every experiment was started with pre-growth in a growth unit for about20days to choose uniform plants.After pre-growth,50uniform plants were divided into10groups ofﬁve.Before planting in the growth units,the fresh weight of each group was measured.For each experiment,ﬁve harvests were made with an interval of5–7 days,depending on relative growth rate(g/g/day). Four groups were collected at theﬁrst,two groups at the second and third,and one group at the fourth andﬁfth harvest.At each harvest the fresh and dry weights of the total plants,roots,shoots and stems were determined.The total leaf area in each group was measured using an image analysing system(video/computer image analysis, Image Access,Micro Macro Bildanalys,Gothen-burg,Sweden).The leaf area ratio(cm2/g/plant DW),speciﬁc leaf area(cm2/g/leaf DW),speciﬁc root length(the longest root divided by root dry weight,m/g root DW),stem length,node number and internode length(stem length divided by node number)and dry matter allocation were calculated from each harvest for every experiment.Since the experiments were performed at the exponential growth phase,plant physiological states were ex-pected to be constant with time during the whole experimental period.Therefore,every harvest was taken as a replicate except for stem length,node number and internode length for which the data from the last harvest are presented.The data were subjected to ANOVA analysis using the Stat-graphics program.3.Result3.1.Relati6e growth rateFig.1shows relative growth rates of all plants from regression analysis.The constant relative growth rates were achieved for all plants,indicat-ing that a steady-state was maintained during the experimental period.The grafted GR/rol A1,GR/rol A2and GR/rol B plants grew at a similar relative growth rate to that of the GR/M26plants under non-limiting nutrient conditions(Fig.1),suggesting that the transformed rootstocks did not signiﬁcantly inﬂu-ence the relative growth rate of the grafted plants.3.2.Leaf area ratio and speciﬁc leaf area Neither the leaf area ratio nor the speciﬁc leaf area value of the GR/rol A1,GR/rol A2and GR/ rol B plants were signiﬁcantly different from thoseFig. 1.Relative growth rates(RGR)of the grafted apple cultivar Gravenstein(GR)onto the untransformed rootstock M26(M26)and the transformed M26with rol A(rol A1and rol A2)and rol B(rol B)genes under non-limiting conditions with steady-state nutrient supplies.The RGR(g/g DW/day) values followed by the same letter do not differ signiﬁcantly at P=0.05.L.-H.Zhu,M.Welander/Plant Science147(1999)75–80 78Table1Leaf area ratio(LAR,cm2/g/plant DW)and speciﬁc leaf area (SLA,cm2/g/leaf DW)of grafted apple cultivar Gravenstein (GR)onto the untransformed apple rootstock M26(M26) and the transformed M26with rol A(rol A1and rol A2)and rol B(rol B)genes under non-limiting conditions with steady-state nutrient supplies aPRIVATE Plant SLALAR177.996.85a112.496.85aGR/M26GR/rol A1110.994.47a193.796.67a175.797.64a GR/rol A2105.393.69a99.694.47a173.994.03a GR/rol Ba The values are given as means9S.E.Values followed by the same letter do not differ signiﬁcantly at P=0.05.Table3Dry biomass allocation,expressed as leaf DW/plant DW (L/P),shoot DW/plant DW(S/P)and root DW/plant DW (R/P),of grafted apple cultivar Gravenstein(GR)onto the untransformed apple rootstock M26(M26)and the trans-formed M26with rol A(rol A1and rol A2)and rol B(rol B) genes under non-limiting conditions with steady-state nutrient supplies aPlant L/P S/P R/P0.5890.02a0.2690.01a0.1690.02a GR/M260.5890.01aGR/rol A10.2690.01a0.1690.01a0.1590.02a0.2690.01aGR/rol A20.5990.02a0.5690.01aGR/rol B0.3090.01a0.1490.02aa The values are given as means9S.E.Values followed by the same letter do not differ signiﬁcantly at P=0.05.of the GR/M26plants under non-limiting nutrient conditions(Table1).3.3.Speciﬁc root lengthThe speciﬁc root length value of the grafted GR/rol A1and GR/rol A2plants was greatly re-duced compared to the GR/M26plants,while no differences in SRL were found between the GR/ rol B and GR/M26plants(Table2).3.4.Dry matter allocationDry matter allocation of the grafted GR/rol A1, GR/rol A2and GR/rol B plants were similar to that of the GR/M26plants(Table3).3.5.Stem length,node number and internode lengthBoth stem length and internode length of the GR/rol A1plants were reduced compared to the GR/M26plant,while the GR/rol A2and GR/rol B plants did not show different stem length and internode length compared with the control plants (Table4).4.DiscussionIt has been reported that the rol B gene is partic-ularly efﬁcient in promoting root formation in different host plants[9,11,17–19].Our previous studies have shown that the introduction of the rol B gene into the apple rootstock M26increased not only the rooting ability in vitro,but also the rooting ability ex vitro by conventional cuttings [6,7].The rooting percentage of conventional cut-tings was about90without auxin treatments[7]. Moreover,the introduction of the rol B gene into M26also caused a reduced relative growth rate compared to the untransformed M26plants under non-limiting nutrient conditions[8].However, from the present study,the grafted GR/rol B plants did not show a reduced relative growth rate compared to the control plants GR/M26.This may suggest that the total growth of the grafted plants is not directly related to the relative growth rate of the rootstock under non-limiting nutrient conditions,at least not at the exponential growth phase.The introduction of the rol A gene into the apple rootstock M26resulted in different relative growth rates under non-limiting nutrient conditions.The clone rol A1had a signiﬁcantly reduced relative growth rate,while the clone rol A2displayed a similar relative growth rate compared to the un-transformed plants.Moreover,even though both clones showed a tendency of reduced internode length,it was more pronounced for the cloneTable2Speciﬁc root length(SRL,m/g/root DW)of grafted apple cultivar Gravenstein(GR)onto the untransformed apple rootstock M26(M26)and the transformed M26with rol A (rol A1and rol A2)and rol B(rol B)genes under non-limiting conditions with steady-state nutrient supplies aSRL PRIVATE PlantGR/M26 5.1091.53b GR/rol A1 2.0291.02a GR/rol A2 2.2190.94a GGR/rol B 2.5290.84aba The values are given as means9S.E.Values followed by different letters differ signiﬁcantly at P=0.05.L.-H.Zhu,M.Welander/Plant Science147(1999)75–8079 Table4Stem length,node number and internode length of grafted apple cultivar Gravenstein(GR)onto the untransformed apple rootstock M26(M26)and the transformed M26with rol A(rol A1and rol A2)and rol B(rol B)genes under non-limiting conditions with steady-state nutrient suppliesStem length(cm)PRIVATE Plant Node No.Internode length(cm)11GR/M26 1.9020.9GR/rol A115.111 1.3719.1GR/rol A210 1.911120.9 1.90GR/rol Brol A1[8].However,when the two transformed clones were used as rootstocks for the cultivar Gravenstein in this study,none of them signiﬁ-cantly reduced the relative growth rate of the grafted plants.On the other hand,the GR/rol A1 plants did show both reduced stem and internode lengths compared to the control plant GR/M26. This further indicates that the relative growth rate of the rootstock has no direct relationship to the dwarﬁng characteristics of the grafted plant.Our previous studies on the effect of rootstocks and scions on growth characteristics of grafted apple plants also support this assumption[20].The re-duction of internode length of the GR/rol A1 plants is apparently related to the reduced stem length of the plants.RT-PCR analysis showed that the clone rol A1had a higher expression level of the rol A gene than the clone rol A2(Xue et al., unpublished).This may explain the above differ-ences in phenotype of the two rol A clones. However,the speciﬁc root length reduced sig-niﬁcantly for both GR/rol A1and GR/rol A2 plants compared to the control plants.This may be a good characteristic of the transformed root-stocks rol A1and rol A2for potential commercial use.The importance of root size and root mor-phology for nutrient uptake has been demon-strated in a number of mathematical models and in some experiments[21].One of the main factors inﬂuencing nutrient uptake by roots in soil is root size(mostly root length).A high SRL favours the uptake capacity and competitive ability of the plant and vice versa[21].If this is so we may expect that the reduced root length of GR/rol A1 and GR/rol A2plants will cause a reduced tree size or dwarﬁng effect under limiting conditions.The main reason why the clone rol A2did not show any dwarﬁng characteristics,i.e.shortened stem length and internode length,is probably due to the lower gene expression compared to the clone rol A1.Another reason might be due to the special experimental system employed in this study.Since the plants were grown under an aeroponic system with non-limiting nutrient supply,the speciﬁc root length value may not be as essential for nutrient uptake as that in limiting nutrient situations.As the present results were obtained with the aeroponic experimental system and the plants were still at a very young age considering the apple as a perennial plant,it is necessary to conduct experi-ments under limiting conditions both in the green-house and in theﬁeld to further evaluate these transgenic rootstocks before aﬁnal conclusion can be drawn for commercialisation. AcknowledgementsWe would like to thank Anna Holefors for providing the transformed rol A plants and Krzysztof Roszko for his help with some of the experiments.We are also thankful to all the staff in the Biotron in Alnarp,Sweden,for their techni-cal support during the whole experimental period. The Swedish Research Council is gratefully ac-knowledged for theﬁnancial support. 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