Apple Tree: Important Tasks at Pea Stage

 In my previous post I have discussed about Apple tree: Important Tasks at Petal Fall Stage. Now the time is approaching for Pea Stage of fruit development in apple. 

During the pea stage of fruit development in apples, the fruitlets are about the size of a pea (typically 6–10 mm in diameter). This is a critical period for several orchard management practices that impact fruit size, quality, and overall tree health as this is the period when cell multiplication takes place. Here are the important tasks to be carried out at this stage:

🌱 1. Thinning

• Why? Reduces fruit load to improve fruit size, colour (Exposure to light), and return bloom for the next year.
• How it is to be done?
• Chemical thinning is common at this stage (e.g., using NAA, NAD, or carbaryl).
• Follow with manual thinning later if needed.
• The pea stage is ideal because the tree hasn't committed all resources yet.

🛡️ 2. Pest Management

• Key pests to monitor and control:
• Fruit Borer (Helicoverpa) (1st generation egg hatch begins around this time)
• Aphids, leafrollers, and mites
• Use IPM practices, pheromone traps, and targeted insecticides based on monitoring.

🍄 3. Disease Management

• Critical for controlling:
• Apple scab
• Powdery mildew
• Maintain a protective fungicide program and remove infected shoots.

💧 4. Irrigation Management

• Young fruitlets need adequate water to develop properly.
• Begin regular irrigation scheduling based on soil moisture and weather.

🧪 5. Nutrient Management

• Foliar feeding (e.g., calcium sprays) may begin to improve fruit quality and prevent disorders like bitter pit.
• Continue soil or fertigation-based nutrient supply as per leaf or soil analysis.

✂️ 6. Training & Pruning Touch-Ups

• Light summer pruning may begin:
• Remove competitive and vigorous upright water shoots (suckers)
• Improve light penetration (better spur development for next year) and air circulation (Better disease control)

📋 7. Monitoring & Record-Keeping

• Record fruit set, thinning effectiveness, pest/disease pressure, and phenological stages for future reference and management decisions.

 

Apple Tree: Important Operations at Pink Bud Stage

Critical Stages for Apple Spray Schedule

The Pink Bud Stage in apple trees is a growth stage that occurs just before the flowers fully open. At this stage, the flower buds are swollen, and you can clearly see the pink or red petals through the tips of the buds, but the flowers haven't opened yet.

Why Pink Bud Stage is Important?

1. Pest and Disease Control:
• Many pests and diseases are active around this stage (e.g., aphids, scab, Marssonina, Powdery Mildew).
• It's a critical time for applying fungicides and insecticides to protect the developing flowers.
2. Nutrient Management:
• Applying foliar nutrients like calcium, boron, or zinc can improve fruit set and quality.
3. Frost Sensitivity:
• Buds at this stage are sensitive to frost damage, so frost protection may be needed.

The pink bud stage is crucial for ensuring healthy blossoms and good fruit set, so proper management at this time can make a big difference in your apple harvest.

At this stage focus on these tasks:

🌸 Care and Maintenance

• Watering: Make sure the soil has enough moisture but avoid overwatering.
• Frost Protection: Use sprinklers, smoke at night, or wind machines if frost is expected.

🌿 Pest and Disease Control

• Fungicides: Spray to prevent diseases like apple scab, powdery mildew.
• Insecticides: Use if pests like aphids, mites, or leafrollers are present. Avoid harming bees.
• Monitoring: Check for pests like thrips, archips (caterpillars) and aphids to plan future sprays.
• For detailed Integrated Spray Schedule you may check e-udyan portal of Department of Horticulture, Govt of Himachal Pradesh.

🌱 Nutrition

• Foliar Feeding: Spray nutrients like calcium, boron, or zinc, if needed i.e. if soil test reports indicate deficiency of these nutrients.
• Fertilizing: Avoid heavy nitrogen fertilizers—these can cause too much leafy growth and invite foliar diseases

In next Post we will be talking about Role of Pollinators in Apple Pollination.

Fruit Tree Problems: Multiple Choice Questions on Cocoa Diseases

 Previous post during last year was on Fruit Tree Problems: MCQs on Arecanut Diseases. This year I am continuing with other set of questions. You may answer these in comment section

Q 1 Phytophthora palmivora causes _____________________ disease of cocoa

a. Seedling die back	c. Black pod disease
b. Stem canker	d. All the above

Q 2 White thread blight is caused by

a. Marasmius scandens	c. Botryodiplodia theobromae
b. Colletotrichum gloeosporioides	d. Oncobasidium theobromae

Q 3 White thread blight spread through

a. Contact of branches	c. Contact of plant to plant
b. Contact of mycelium	d. Dead leaves carried by wind

Q 4 Characteristic symptom(s) of Black pod diseases of cocoa

a. Appearance of brown spots on pods	c. Both a and b
b. Discoloration of brown spots & infected beans	d. None of these

Q 5 Favourable conditions for black pod

a. High density plants accompanied with shady location with cool temp.	c. HDP with RH upto 90% and Temp 30-35oC
b. High density plants in rainy weather with high temperature	d. HDP with RH >95% and Temp 30-35oC

Q 6 Charcoal pod rot of cocoa is caused by

a. Marasmius scandens	c. Botryodiplodia theobromae
b. Colletotrichum gloeosporioides	d. Oncobasidium theobromae

Q 7 Asexual fruiting body produced by Botryidiplodia theobromae

a. Acervulus	c. Pseudothecium
b. Pycnidia	d. Apothecium

Q 8 Causal organism of cocoa swollen shoot is

a. Phytoplasma	c. Bacteria
b. Virus	d. Fungus

Q 9 Characteristic symptom of cherelle rot is

a. Shrunken infected stalk with mummified fruit	c. Both a. and b.
b. Brown discolored beans under high humid conditions	d. None of these

Q 10 Vascular streak dieback of cocoa has been reported only from

a. Tamil Nadu	c. Karnataka
b. Kerala	d. Telangana

 

Apple Tree Diseases: White Root Rot Management

This is in continuation to my earlier post on Diseases of apple: White Root Rot Pre-Disposing Factors. This disease is generally appear in clay laom or loam soil having neutral pH. Mainly characterized by white thread like mats in the feeder root and bark that has rotten completely. Always get it diagnosed from an expert eye or one must consult some experienced farmers or a plant pathologist. Since it’s a soil borne disease, it should be managed in holistic way

1.     Phytosanitation: Free water or flood irrigation high moisture content in basin is major pre-disposing factors for the disease to spread. So keep the cultivation area free of diseased material like diseased bark and roots, etc. The cleanliness reduces the primary inoculum of the disease causing agents. This simple principle should be followed even if we don’t see primary symptoms. This is the best way to manage the diseases on small farms and helps in reducing the costs.

2.     Cultural Practices: Alter the environment in which disease is appearing i.e. high moisture level in the basin and nearby trunk. Improve drainage from the basin area. The basin area should be enriched with organic matter in the form of FYM or vermicompost, mulching with dry grass etc. This helps in building up saprophytes that in-turn act as biological control agents. These practices remove the primary inoculum as well as modify the environment for disease proliferation again without enhancing the cost to a greater level.

3.     Biological Control: Introduction of biological control agents in the soil is always being a good idea. Trichoderma viride, and its variants help the plant in fighting with plant pathogen and grow healthy with a little cost. If consortium of different soil inhabiting biocontrol agents is available it will help better in managing the disease.

4.     Chemical Control: Agrochemicals should be the last priority to manage the disease and that too after the proper diagnosis. As the application of a wrong chemical will not only worsen the situation but also pollute the soil and soil microflora. i.e. soil health. In turn increase the cost without preventing the damage caused by the insect-pests or disease. Since the disease caused by Dematophora necatrix this can easily be checked by carbendazim.

In my coming post I shall be discussing about pre-mature leaf fall of apple.

Apple Tree Diseases: Powdery Mildew Disease Cycle

This post is in continution to my previous post on Diseases of Apple: Powdery Mildew. In this post we are going to discuss about how disease causing propagules overwinters (survive) and cause primary and secondary infections. 

Disease cycle:  

The powdery mildew fungus overwinters as mycelium in infected buds or as cleistothecia on the surface of infected twigs. Infected terminal buds are more susceptible to winter injury than healthy buds, typically bud break in the spring is 5-8 days later than healthy buds, and are more susceptible to spring frost than healthy buds. In fact, healthy buds may survive at temperatures 2-10^oC colder than infected buds. As a result, many infected buds will not survive through a cold winter. This is important to keep in mind because a hard winter can dramatically reduce both disease pressure and the need for control measures during the subsequent season. The survival rate of infected buds is less than 5 per cent when temperatures drop below –24^oC and, although not well studied, it appears that temperatures around –12^oC will kill the mycelium in infected buds and allow the bud to produce healthy leaves. The cleistothecia, which form the sexual stage of the fungus and produce ascospores, apparently do not play an important role.

Mycelia in infected buds produce conidia to initiate primary infections and these infections can be found as early as the tight cluster stage. There is often an abundance of susceptible tissue for the conidia to infect because infected buds break later than healthy buds. Conidia are disseminated by wind and can infect young leaf tissue, blossoms, and fruit. Leaves become increasingly resistant to infection as they age and become nearly immune once they have matured, although infection can occur through injuries on older leaves. Symptoms may develop as early as 5 days after infection. Numerous secondary cycles can occur under favorable conditions and, like many powdery mildews, cooler temperatures rather than relative humidity drive early secondary infections. Like other powdery mildews, P. leucotricha exhibits a diurnal periodicity in that the highest concentration of airborne conidia is found from midday to early afternoon. Infections that result in fruit russet occur primarily during the pink stage of bud development.

Apparently, infection of lateral and fruit buds occurs within 1 month after they are formed. The infections remain latent until bud break the following spring where they will serve as the initial source of inoculum. The lateral buds are susceptible to infection longer than the terminal buds, however, it is the terminal buds that are the likely source of overwintering of the fungus as infection can be greater than 50 percent by terminal bud set.

In coming post we are going to discuss about the management of the disease

Apple Tree Diseases: Powdery Mildew

Diseases play an important role in low productivity of any crop in the form of yield losses. Generally about 33% losses are due to diseases and insect pests. There are some diseases which not only impair with the yield losses but these also contribute towards poor quality of the produce. The question now arises that, What is Disease?: 

Disease is an impairment of health or a condition of abnormal functioning.

Diseases of Apple

Powdery Mildew
Collar rot
White Root Rot

Premature Leaf Fall
Sooty Blotch and Fly Speck
Apple Scab
Apple Mosaic Virus

In this post we are going to talk about the powdery mildew disease of apple. This disease is very common in Kinnaur district of Himachal Pradesh as dry weather plays an important role in the appearance of the disease.

Description: The disease infects leaves, blossoms, green shoot, and the fruit. On the leaves, the fungus can appear as felt-like patches or as a solid mat on the surface, particularly on the undersurface of the leaf. Initial infections on the underside of the leaf may cause chlorotic patches or spots to occur on the upper side of the leaf. This symptom, however, is not unique to powdery mildew so inspection of the underside of the leaf is necessary to confirm that powdery mildew is the cause of these symptoms. Under favorable environmental conditions, the disease spreads over the entirety of the leaf and progresses down the petiole on to young, green shoots. Infected leaves tend to crinkle, curl, or roll upwards along the edges giving them a narrow appearance. If the infection is severe, infected leaves will usually drop prematurely during the summer.

Shoot infections are the typical result of overwintering infections of the fungus in buds. When the terminals push in early spring, the fungus grows along with the new succulent growth and infects this tissue immediately. These shoots may be killed outright in the spring, or may survive throughout the season and die in late fall or winter. The initial growth of the fungus on newly infected twigs appears powdery white but eventually turns a darker brown. Small black fruiting bodies, called cleistothecia, can appear in the mycelial mat and function as the source for sexual reproduction and the eventual production of ascospores.

The blossoms, petals, sepals, receptacles, and peduncles may become infected and covered with the fungus. Blossom infections are less common but are important because infected blossoms will either fail to set fruit or produce small, stunted and/or russetted fruit. These fruit are unmarketable for fresh market consumption. 

In my next post I shall be talking about the 
Disease Cycle of Powdery Mildew, 
Management of Powdery Mildew

Apple Tree: Training Systems in Intensive Apple Cultivation: Vertical Axis

This post is in continuation of the series on Training Systems in Intensive Apple Cultivation This post explains about the Vertical Axis or French Axis training system 

The vertical axis (VA) system

The vertical axis (VA) system has been touted by some growers as the next logical step from free standing central leader trees to high density supported systems. The main reason cited is the great similarities between the systems and the low emphasis on limb manipulation by tying. There are ladders used in picking, but with a flat tree wall at ladder height it is quite fast and simple to manage ladders.

Even though the VA system is one of the taller systems used in high density supported systems, there is still a critical need for lower limb development. These lower limbs will form a fruiting table yielding perhaps 60% of the crop and must be established before the trees should be allowed to grow taller. Proper development of the bottoms of the tree will allow 75% or more of the fruit to be picked from the ground. Cultivars that have a high requirement for light (e.g. McIntosh) are well suited to this system. Other cultivars like Gala, Goldrush, Golden Delicious and Empire have a growth habit highly suited to this system.

VA systems allow trees to grow taller than SS systems. The system basically consists of one or more high tensile steel wire(s) drawn tight and supported 2 - 3 m above the ground by a series of in-line posts spaced 9 to 15 m apart. The closer the spacing for the inline posts, the higher the degree of stability of the support system under strong wind or high cropload conditions. 

Individual trees in the row are supported by vertical leader supports that reach up to the top support wire. The tree consists of a conical, or "Christmas tree" shape and grown up to 3.5 - 4.0 m tall. The leader is not pruned until the tree reaches its full height. Shoots arising on the side of the axis or trunk close to and competing with the leader are removed as they arise or during the dormant pruning season. Side branches on the leader are renewed on a periodic basis.

The VA support system is somewhat more complex than the SS to install. It does require a high level of skill to build the support system and be sure it is adequate to hold the trees and crop load. A post failure in this system can result in the loss of several trees. The standard anchoring system now in use is the "auger anchor" which is screwed into place. Posts are generally pounded or watered (water gun) into the ground.

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Apple Tree: Training Systems in Intensive Apple Cultivation: Slender Spindle

This post is in continuation of the previous post on Training Systems in Intensive Apple Cultivation: Trellis. This post explains about the Slender Spindle training system further modification of spindle bush training system.

Slender Spindle:

This is the system preferred by growers who wish to work exclusively from the ground and are not confident in building wire support systems. The slender spindle (SS) consists of an individual support post at every tree.

Slender Spindle Support System:

The post should be 2.4 - 3 m in length and of pressure-treated wood, concrete or metal to ensure it lasts the life of the orchard (perhaps 12 - 18 years). A diameter of 4 - 6 cm is preferred, since risk of frost heaving increases with larger diameters. The depth of the post in the ground should be 60 - 90 cm for stability leaving 1.5 to 2.5 m above ground. A common mistake is to have insufficient post height above ground.

Slender Spindle Training Pruning:

The tree is trained to a slender bell, or pear shape with the bottom whirl of branches acting as a permanent fruiting table. The leader and top of the tree is kept quite weak to contain height. Renewal pruning of mature trees consists mainly of removing 2 - 3 of the largest diameter branches on an annual basis during the dormant season.  Tree height does not exceed 2 - 2.5 m.

In the next post I shall be discussing about the Vertical Axis or French Axis training system. This system is followed mainly in France having average productivity of about 42 Tonnes per Ha.

Apple Tree: Training Systems of Apple Trees in Intensive Orchards

The number of apple trees per acre in new orchards has gradually been increasing. Orchard intensification is motivated by the desire to produce fruit early in the life of the orchard to rapidly recover establishment costs. Intensification is possible by using dwarfing rootstocks that control tree size, induce early cropping, and produce large quantities of fruit relative to the amount of wood produced.

Apple trees grown on dwarfing rootstocks have shallow or brittle roots systems and trees grew poorly and often leaned or fell over. Therefore these plants require support systems. However, Intensive orchard systems are more profitable than traditional low-density orchards on semi-dwarfing rootstocks. However, because the establishment costs for intensive orchards are high, trees must be trained and pruned properly to induce and maintain high yields.

Motivation for orchard intensification.

The primary reasons for orchard intensification include:

1.) early fruit production, and
2.) reduced pruning and harvest costs of mature orchards.

Yield is positively related to the amount of sunlight intercepted per acre. Profit, which is influenced by yield as well as fruit size and quality, is probably at an optimum when an orchard intercepts about 70% of the available light. Traditional orchards, using vigorous rootstocks, were typically planted at a spacing of about 22 feet x 16 feet with 132 trees per acre. For the first five or six years after planting, fruiting was discouraged to promote vegetative growth so trees would fill their space as rapidly as possible. The first crop was usually harvested four or five years after planting, but high yields were not obtained until trees finally occupied their allotted space. Maximum yields did not occur until about 12 to 14 years after planting.

Intensive orchards are typically planted at narrow spacing depending upon the training system adopted but one thing is very clear that a small crop is often harvested the year after planting, because trees have so little space to fill, peak production is usually achieved during the 6th or 7th year after planting. Once trees fill their allotted space, maximum yields are similar for all types of orchard systems. Because the primary advantage of intensive orchards is early fruit production, these orchards should be planted only on excellent sites with a low probability of crop loss due to frost or hail.

Intensive orchard training systems.

The three basic types of training systems used for intensive orchards are

1. "Trellis,"
2."Slender Spindle," and
3."Vertical axis or French Axis."

There are many modifications of each system, and orchardists will need to adapt a system to suit their own particular situation. The basic systems will be discussed in coming posts

Apple Tree: High Density Apple Plantations: Why?

In my previous blogs I discussed about high density plantation and rootstocks, clonal rootstocks. Though I have written about the productivity, but farmers must understand what does this productivity means? For this purpose I tried to compare the area harvested, production and yield for 2006 to 2010 (five years) for six countries Viz. China, France, India, Italy, New Zealand and USA. Graphs prepared for visualizing the impact of high productivity. You can go through these graphs and then decide why HDP is necessary? The data was obtained from www.fao.org (FAOSTAT).

The data presented above indicates that India possesses second largest acrage under apple plants among the six countries compared, where as Italy possesses only one sixth of its acrage but when production is compared with, India and Italy has at par production. France shows maximum productivity and India shows lowest productivity. Further our orchards are becoming old and senile that warrents us to move with a planing and that too we have to face replant. We have only one option if we want to maintain our production or enhance the production and quality i.e. HDP.

In coming posts I shall be discussing about training systems for HDP Apple.

Apple Tree: High Density Plantation: Apple Rootstock

This post is in continuation to my previous post on High Density Plantation: Advantages of smaller trees.

What is rootstock?

Rootstock is the root system and a small proportion of the lower trunk of most apple trees. Grafting the genetically distinct fruiting part of the tree, the scion, on the rootstock forms whole tree. Occasionally a third genetically distinct component, an interstock or interstem, is grafted between rootstock and scion.

Why rootstocks are used?

Its really difficult to propagate the scions directly, but the rootstocks can be propagated easily that’s why rootstocks are used in apple propagation whether seedling or clonal rootstocks. Next question comes to the mind that why clonal rootstocks when seedling rootstocks are available and are propagated easily. Its true that seedling rootstocks can be propagated easily but these vary in genetic make up because its a sexual propagule, therefore it is bound to produce a different reaction to the scion. This means that you can not expect the plant to produce the same quality as of the parent. Whereas the clonal rootstock is produced through vegetative means thus have same genetic print that gives assurance that reaction to the scion will be the same that means there is most likely same quality of the plants and fruits can be produced.

In coming post I shall be discussing about Advantages of clonal rootstocks

Apple Tree: High Density Plantation: Advantages of smaller trees

I discussed about Trichoderma with respect to its role in plant health management. In my previous posts I have discussed about low productivity in apple especially in our perspective. This low productivity in Himachal is because of many reasons discussed in previous posts that are to be dealt with technological back up. This requires lot of motivation of the farmers to adopt high density plantation on clonal rootstock but with this there is a great need for the technologocal backstoping. My core feeling is that what ever we are producing is not enough since if we check out the production data of our state it is hardly touching 11 T per hectare that too once or twice in the histroy of apple production but if we check out the average then it is hardly 4.5 T per hectare. Whereas countries like NewZea Land and Italy producing fruit to a tune of 40 T per hectare this makes us to review our strategies and to findout the way to increase our production. There are some farmers who are doing a very good Job in this regard they are trying to develop there own system to keep pace with the industry of apple production among these I must mention here that Mr. Vikram Singh Rawat in Karsog Valley is putting all his efforts to produce the trees on clonal rootstocks further he is putting lot of efforts in bringing the farmers under the umbrella of organic farming and high density plantation. In this series I feel that it is important to mention the name of Mr. Rajesh Thakur of Mahog, Mr. Rajender Kaushal of Chamanpur, Mr. Arun Bansal of Ruhni, Mr. Diljeet Singh Ghumman of Bakhrot, besides Mr. Dinesh Primta of Chaupal area, Mr. Neetu Dharma of Kotgarh and Rajender Chauhan of Kotkhai are the one those are working hard to make this high density apple plantation a reallity. This is a list where I know these farmers either personnaly or through my close connections. Many other farmers involved in the high density plantation this situation warrents us that we must put our steps forward to support these farmers in achieving their endeavours. That was the reason to bring out this topic ahead of disease and pest management in apple that was in planning well before persuing this blog.

In this blog I shall first cover the advantages of small trees these are as follows:

1.    Reduce pruning costs

2.    Less spray per unit fruit

3.    Better spray coverage

4.    Smaller, less expensive equipment

5.    Quicker fruiting

6.    Lower harvesting costs (no ladders)

7.    Labour prefers smaller trees

8.    Easier to mechanize

After looking on these let us see how many of farmers are getting motivation...............
In coming posts I shall be dealing with the Various rootstocks and scions that can be used in high density apple plantations