top of page
Writer's pictureA. N. Ganeshamurthy

Sampling of Leaves in Fruit Trees

We present this video to you about how to collect leaf samples from fruit trees for knowing the nutritional problems in your orchards.


Namaskar from soulofkrishi. We have come before you with a very useful video on how to collect leaf samples of fruit trees for knowing the nutritional problems in the orchards.

If you like this video, please subscribe to our YouTube channel and share with all your friends.

Nutrient deficiency and disorders are very common in tree crops particularly fruit crops. Quantifying nutrients in soils and trees tissues eliminates guesswork when adjusting a fertilizer program and deciding what to apply and how much to apply. To understand the problem before correcting it we need to go for either soil test or leaf analyses and decide whether to apply to soil or go for a foliar spray. So both soil testing and leaf analysis are important in deciding fertilizer programme of an orchard.

Soil analysis is helpful in formulating and improving a fertilization program because soil testing measures organic matter content, pH and extractable nutrients. However, fruit crop farmers cannot rely on soil analysis alone to formulate a fertilizer program or to diagnose a nutritional problem in orchards. Leaf sample analysis and observations of leaf deficiencies and toxicities should also be used to confirm the nutritional problems in the orchards. Soil pH greatly influences nutrient availability. Some nutrient deficiencies can be avoided by maintaining soil pH between 5.5 and 7.5. Therefore the single most useful soil test for a fruit crop is for soil pH.

Why Leaf Analysis?

The goal in Leaf Analysis is to adjust fertilization programs so that nutritional problems and their costly consequences are prevented. Fruit crop leaf testing has established its reliability as a management tool, but sampling guidelines should be followed precisely to ensure that analytical results are meaningful.

Leaf tissue analysis

• Tells us if the tree has had a sufficient supply of essential nutrients.

• Confirms nutritional deficiencies, toxicities or imbalances

•Identifies hidden toxicities and deficiencies when visible symptoms are not present.

• Evaluates the effectiveness of fertilizer programs.

• Tells you what fertilizer application you are following is correct or needs a correction.

• Determines the availability of elements not tested for by other methods.


Leaf tissue analysis tests all the factors that might influence nutrient availability and uptake. It also tells about the concentration of human and animal health nutrients and also the toxic pollutant heavy metal content in trees. Correct sampling gives you the best useful results.

Leaf Sampling Considerations

Procedures for proper sampling, preparation and analysis of leaves have been standardized for all major fruit crops grown in India. One has to strictly follow the sampling procedures for a reliable test report and fertilizer program adjustments. Farmers must take at most care from the time leaves are selected for sampling to the time they are received at the laboratory for analysis.

Farmers must strictly follow these specific sampling instructions during sample collection.

Collected samples from each block of trees of the same age,

If you have different varieties of the same fruit crop then separately collect sample variety wise

If rootstocks are different then collect samples rootstock wise

Collect the leaf samples from recently matured leaves so that the nutrient concentration has stabilized and do not collect from water shoots or suckers

Make sure that the sampling branches are not contaminated with dust or soil, mechanically damaged, insect damaged, or disease infested.

As for as possible Select leaves approximately at eye level from limbs that are 45 to 60 degree angles away from the trunk

While sampling farmers must avoid sampling of these leaves

  1. If leaves are showing deficiency symptoms then do not take such leaves

  2. If the tree is infested with nematodes, insects or diseases and the roots are damaged then avoid taking samples from such trees

  3. Avoid samples from trees that are under stress due to disease

  4. If trees are under flooded condition due to excess rain or facing drought or if trees are affected by drifting spray of herbicides and excess pesticides then do not take samples from such trees.

With these basic instructions in mind let us move to orchards for sampling.

Mango

For nutritional diagnosis in mango the best time would be in shravanmas that is july to august. Randomly select 10 to 15 trees per hectare in the orchard and select leaves which are 5 to 6 months old. Locate 10th leaf from youngest leaf in leaf whorl and collect 40 to 50 such leaves along with petioles per ha. and transfer to sampling bag.

Lychee

Lychee and mango have similar canopy although lychee is more robust. But leaf sampling in lychee is different. Here sampling is done 1-2 weeks after flower panicle is initiated. Select first healthy leaf whorl under the panicle and select leaflets from 3 to 5 positions starting from uppermost fully opened leaf. Sample 20 trees and collect about 160 leaves per ha. and transfer to sampling bag

Citrus group(Orange, lime, lemon, mandarin)

To sample leaf tissue, on the tree select randomly 10 to 15 trees and locate the spring growth flush (3 to 5 months old) from non-fruiting branches. Collect leaves from the 1st leaf of the shoot and collect 40 to 50 such leaves/ha. and transfer to sampling bag.

Guava.

Guava yields twice a year and in some places throughout the year. Hence you can collect leaf samples either in August or December. Select randomly 10 to 15 trees and locate the 3rd pair of recently matured leaves and collect 40 to 50 such leaves/ha and transfer to sample bags.

Custard Apple

Custard Apple is pruned before leaving for fruiting. Hence sample may be collected before pruning in December or after pruning and sufficient growth of leaves in July-August. Hence you can collect leaf samples either in August or December. Select randomly 10 to 15 trees and locate 5th leaf from apex from from 2 months after new growth. Collect 40 to 50 such leaves/ha and transfer to sample bags.

Grapes

Sampling in grapes is different from other fruit crops. Here instead of leaf we sample petioles. Further we may get leaf petiole tested for yield and also for quality. As in other crops in grape garden also select randomly 10 to 15 vines per ha. Locate 5th petiole from the base at bud differentiation stage and collect about 100 to 150 petioles for yield forecast. And collect about 100 to 150 petioles opposite of first or second flower for fruit quality purpose and transfer to sample bags.

Fig

In fig sampling is done during July-August by selecting 10 to 15 trees randomly per ha. Locate mid shoot from current growth and collect 40 to 50 fully expanded leaves and transfer to sample bags.

Banana

Banana is different from all other fruit crops. It has a very bigh leaf lamina and complete leaf cannot be sampled. In this case 20 to 25 plants In July-August and locate third open leaf from top. Cut 10cm wide sample strips from at about half way along the leaf on each side of the midrib and transfer to sample bags.

Papaya

Like grapes in papaya also petiole is sampled for analysis. Since plant population is more per ha. we need to sample about 20 to 25 trees in papaya. When the plant is six months old randomly select 20 to 25 trees and locate 6th petiole from apex and collect about 40 to 50 petiole sample, cut in to pieces mix well and transfer a portion of the sample to sample bags.

Pomegranate

In pomegranate since fruiting period varies from orchard to orchard we can sample leaves when flowering starts after ethereal spray in April for February crop and August for June crop. Since plant population is more per ha. we need to sample about 20 to 25 trees in pomegranate. Randomly select 20 to 25 trees and locate 8th leaf from apex. Collect 100 to 150 leaves and transfer a portion of the sample to sample bags.

Apple, Peach and Plum

All the three crops are temperate fruits and are deciduous. Here we need to collect when the crop has complete leaves on the trees. So sampling is done in July-August months. Like other crops randomly select 10 to 15 trees per ha. and locate recent mature leaves. Collect about 40 to 50 leaves and transfer to sample bags.

Sample Handling and Analysis:

Farmer who does the sampling must thoroughly wash his hands before sampling to avoid any contamination as they will be handling fertilizers, manures, pesticides and even the soil. At the time of sample collection at the spot itself label the sample by giving crop name, block name or number for each sample along with location and farmers name.

After sample collection bring to farm shed and wash the leaves with clean water and allow for draining of excess water. If possible send the samples immediately to the nearest laboratory for analysis if it can reach within 24 hours. If you feel it takes some time to reach the laboratory then air dry the samples on a clean paper or surface under shade and repack in the sample bags. Send the samples to nearest laboratory so as to reach the laboratory as early as possible. If sending the samples to laboratory takes some time then keep the samples in a refrigerator till it is sent to laboratory.

We have tried to give sufficient tips for a representative sample collection from fruit trees. Farmers kindly use these useful tips and follow the instructions and get full benefit of leaf sample analysis. Hope this video is useful to farmers. Thank you for watching this video

7 views0 comments

Commentaires


bottom of page