groundnuts losses ,All stages of producing peanuts 10

groundnuts losses ,All stages of producing peanuts to trade this product 10

groundnuts losses

groundnuts losses

Overall Losses

3.1 Pre-harvest losses due to diseases and pests

The major diseases of economic importance affecting groundnut crop in the field in India are early and late leaf spots (Cercospora arachidicola [Mycosphaerella arachidis], Phaeoisariopsis personata (M. berkeleyi), rust (Puccinia arachidis), collar rot (Aspergillus spp.), root rot (Macrophomina phaseolina) and stem rot (Sclerotium [Corticium] rolfsii). These ailments cause 13 to 59 percent yield losses during both the rainy and summer seasons. Thrips and jessed are the major pest of groundnut, incidence of these pests is reported significantly higher in the fields not sprayed by the insecticide monocrotophos and pod yield loss due to the pest attack are about 39 percent, which exceeded the economic loss of 12 percent. Crop losses caused by Sclerotinia sclerotiorum, S. minor and Sclerotium rolfsii [Corticium rolfsii] were evaluated in the southern region of the groundnut-producing area in the province of Cordoba, Argentina. Production losses were calculated using the equation: PL=(AY/1.0LP)-AY where PL represents losses, AY the actual yield and LP the proportion of losses. The actual yield is that obtained by the producer while proportional losses are equivalent to the percentage of dead plants (incidence). Furthermore, the incidence of blight and wilting was often higher in groundnut crops where the preceding crop had been groundnut, soyabean or sunflower (Helianthus annuus) than in groundnut crops preceded by sorghum (Sorghum bicolour), maize, alfalfa (Medicago sativa, lucerne), lovegrass (Eragrostis curvula) or grassland. The fact that these diseases are becoming increasingly widespread, together with the losses caused by them throughout the groundnut-growing region are of major importance (Marinelli, et al., 1998).

Among the major arthropods in soil and plant samples taken from groundnut farms in Mali, Burkina-Faso, Niger and Nigeria, termites of the genus Microtermes (Isoptera: Termitidae) were the most abundant and widely distributed species of economic importance. Most of the whitegrub (Coleoptera: Scarabaeidae) and millipede (Myriapoda: Odontopygidae) species identified belonged to the genera of Schyzonycha and Peridontopyge, respectively. Percentages of plants attacked by termites, white grubs and millipedes were 39, 11 and 9 percent, respectively. Yield loss due to termites, which predominantly damaged harvested kernels, was estimated at 10 to 30 percent and was significantly correlated with percentage of plants damaged by termites (Umeh et al., 1999).groundnuts losses

Termites and julids are very serious pests of groundnut in Burkina Faso causing scarring and perforation of pods just before the groundnut harvest. Other more qualitative damages, such as increases in aflatoxin content in the damaged pods are also directly linked to pest attacks. Farmers of Burkina Faso are unable to use chemical control against these pests due to their poor purchasing power. Varietal resistance, which is less expensive and definitely more environment-friendly, offers a better alternative. The relationship between resistance level of varieties and their pod yields is low. For example, NCAC 2243, RMP 40 and NCAC 2240 showed a high level of resistance to combined attacks of termites and julids, they had lower pod yields compared to the other susceptible varieties. Losses due to insect pests in India are sown in Table 19.groundnuts losses

Attempts to manage insect pests often emphasize an understanding of the relationships between insect densities and crop yield loss, because of many variables involved. For instance, the stage of the crop, the weather pattern and the season are all important. Groundnut seedlings are susceptible to relatively low population densities of defoliators, whereas established plants can withstand a considerable degree of leaf loss, more in the rainy season.

groundnuts losses

Table 19. Losses due to insect and mite pests as reported from various groundnutgrowing areas in India.

3.2 Losses due to weeds

In India yield loss in groundnuts due to weeds ranges between 17 and 96 percent. The loss in yield due to competition by weeds may range between 30 to 34 percent. The yield losses are higher in a rain-fed crop and also Spanish compared with an irrigated crop and Virginia runner. Reduction in pod yield because of weed infestation is estimated around 52 percent in Spanish-bunch and 18 percent in Virginia runner types. Weeds in rain-fed Spanish groundnut removes 38, 9 and 23 percent N, P and K per hectare, respectively from unweeded plots. Approaches in weed management include growing suitable intercrops like cowpeas, hand weeding on 15, 30 and 45 days after sowing and chemical methods such as the preemergence application of fluchloralin at 1.0 kg ha^-1, oxyfluorfen at 0.1 to 0.15 kg ha^-1 or pendimethalin at 1.0 kg ha^-1. Adoption of integrated weed management practices such as preemergence application of herbicides coupled with one hand weeding on 20 to 25 days after sowing are the most effective for getting higher yields and net profit (Rajendran and Lourduraj, 1999).

groundnuts losses

3.3 Drought and yield losses

Drought is the main factor inhibiting groundnut production in the semi-arid tropics where most of the developing countries are situated. Drought causes sizable losses, since it deters efforts to combat the nutrient, disease and pest stresses through managerial practices, besides its direct effect in reducing groundnut yields. From the drought resistant trial conducted at ICRISAT three varieties ICGV 87354, ICGV 86014 and ICGV 86124 showed 36 to 54 percent pod yield superiority over the drought-tolerant control ICG (FDRS) 55. Losses due to drought stress may vary based on the intensity and duration of the drought and plant growth stage. For example a mild stress during vegetative phase is beneficial, however stress during pod development phase is highly detrimental to pod development and yield.

groundnuts losses

3.4 Losses due to nutrient deficiencies

The major mineral that is required for the development of groundnut pod is calcium. Calcium deficiency causes groundnut pegs and pods to abort, causing decreased shelling percentages and yield. Environmental factors influencing calcium viability include soil Ca content and soil moisture. Genetic attributes that influence the sensitivity of cultivar to soil Ca supply includes pod size, soil volume per pods (varied by plant growth habit) and pod wall attributes. Where Ca fertilization is not possible, genetic solution to Ca deficiencies is important and breeders need information on the relative importance of these attributes. There are substantial yield losses due to the deficiency of iron, phosphorous and sulphur in groundnut. Kernel development in groundnut is sensitive to boron deficiency, making the crop a good indicator of low boron status in soils. In Thailand, Chiany Maivally and surrounding areas in the dry season of 1984 to 1985, the damage due to the boron deficiency in pod yield was approximated to be up to 28 percent.groundnuts losses

3.5 Losses due to peg drying

A new peg drying problem of groundnut has been observed in about 6 000 ha of the crop grown in sandy soil in the Chirala, Vetapalem and Bapatla regions of the southern coastal Andhra Pradesh, India. The affected plants were slightly stunned and had mottled leaves and blackened pegs and pods. Some pegs were free from lesion but were flaccid. The roots of affected plants appeared bushy. Seeds are generally well formed and often showed hollow heart symptoms in the Vetapalem area. Yield loss due to this problem was estimated at about 30 percent. Low pH, calcium and zinc concentrations in problem soils and improved response of plants to calcium + boron indicated the possible involvement of these abiotic factors in the `peg drying` problem (Sharma, et al. 1995).

3.6 Losses in post-production system

Pod losses during harvesting are substantial (20 to 30 percent), however the losses are more in the Virginia than the Spanish types. The harvesting losses are also depending on the method of harvest and soil moisture content. Excessive soil moisture at the time of harvest also damage the crop quality, on the other hand soil moisture-deficit may increase the pod losses. Therefore, after reaching to the physiological maturity irrigation must be stopped, but at the same time it may also be insured that at the time of digging the soil moisture content in the field is optimum. Soil moisture at the time of digging is most important both to reduce the pod losses due to poor peg strength especially in Virginia types and in situ sprouting of seed due to lack of fresh-seed dormancy in Spanish and Valencia types (Nautiyal et al. 2001). Farmers’ implements for recovering the pod losses during harvest are shown in Figure 33.

 Figure 33:After harvest left over digging the soil with blade attached with a plough is helping in collecting pods.

Lack of awareness and actual skills on groundnut post-harvest technologies have caused significant losses starting from the harvesting to curing, drying and storage. The efficiency of the drying process at the farm level is the most critical stage as this affects subsequent loss in terms of product quality. In spite of the FAO efforts in the “Symposium on Crop Losses” held in Rome in 1967 the information on these aspects is very limited. The conference was intended to examine the international need for factual data on crop losses while suggesting possible ways to obtain reliable information on the losses during harvest and post-harvest processes, Although, the FAO Symposium essentially dealt with pre-harvest losses by biotic agents only and later initiatives amplified this field of interest to include post-harvest losses, as well as losses or constraints caused by abiotic agents. In 1975 a resolution of the United Nations General Assembly established the goal of reducing post-harvest losses by 50 percent with in 10 years. One of the greatest deficiencies in crop loss work, recognized by the 1967 FAO Symposium, was the lack of suitable methodologies. Thus FAO/CAB manuals were published on Crop Loss Assessment Methodologies. The main scope of these manuals is to provide general guidelines about the principles in crop loss work as well as of giving specific detailed examples of methods already available (Chiarappa, 1981). Please see Figure 34.

 Figure 34:Collecting the left over pods after harvest is a regular practice in Saurastra

(Gujarat). Farmers collect about 20 to 30 percent pods of the total yield in this process.

Harvesting usually consists of a series of operations; digging, lifting, windrowing, stocking and threshing, some of which can be combined or eliminated, depending on the system used. In most of the developing countries groundnut production is usually nonmechanized, there are now more opportunity for mechanizing those operations which are either unpopular or have a limited period for optimum results. In developed countries approximately 100 to 150 hectares of a high yielding variety is considered the minimum economic unit for full mechanization including artificial drying. groundnuts losses

Spanish and Valencia types of groundnut usually mature 110 to 130 days after sowing; Virginia types after 130 to 150 days and once the majority of pods are mature delay in harvesting results in substantial loss. The reasons for harvesting loss varies one region to other, but it has been well established that to harvest outside the relatively short optimum period can substantially reduce yield. Too early is as damaging as late. The difference in yield for various harvesting periods in Tanzania is shown in Table 20.

Table 20. Effect of harvesting date on yields of bunch and runner types groundnut in Tanzania.

Source: Weiss, E.A. 1983.

The loss can be higher if the crop is also sown outside the optimum time of sowing. Soil moisture at the time of harvest together with the type of cultivar and method of harvest play an important role in pod losses. Pods are attached to the plant with pegs, on maturity pod get detached from the peg easily, thus during harvest and on lifting a sizeable number of pods remain in situ. Example of pod loss due to the variation in the soil moisture at the time of harvest in an experiment conducted at National Research Centre for Groundnut, Junagadh is shown in Table 21.

Table 21. Pod losses in groundnut during the harvest under two soil moisture regimes in the soils of Saurastra (Gujarat), India.

Source: Devi Dayal, 1985, personal communication.

Harvesting techniques are also important in determining the milling quality of groundnut. Stoking groundnuts normally produces excellent quality haulms and pods but is confined to the developing countries, where machinery is not easily obtainable or where labour is still plentiful. In most of the developing countries plants are left as such to dry in the field after harvest, some method of keeping the pods off the ground is necessary to reduce losses from rotting, termites and moulds. In the literature pod loss in manual harvesting estimated about 10 to 20 percent, where as in the mechanical harvesting pod loss estimated by the USDA are 3 percent in digging and 5 percent during lifting. A survey conducted in Australia concluded that in case of curing in windrows, there is generally a higher incidence of bird, mice and insects damage than in stacking methods. It is estimated that losses in the windrows method are about 10 percent of the total crop in normal years and much higher with adverse weather conditions. It is considered that these losses could be lowered considerably by reducing the length of time that pods are in the windrows (Smyth, 1959). Please see Figure 35. In developing countries groundnut is harvested using diffe../img/ch21/rent types of digger, which essentially weaken the bondage between the plants and soil or may cut the root part. Plants are subsequently collected in small heaps and left in the field for drying. After digging operation the collection of plants and pods is done manually. During harvest some of the pods remain in the soil and one more attempt, usually, is made to pick-up the left over pods. This operation is done manually and consumes lot of time and labour.

Figure 35:After drying groundnut is being transported for threshing by a bullock cart. Blue coloured opener (thresher) is seen in the background.

In Gujarat the summer crop is harvested in June and the rainy season crop in October in both seasons the chances of experiencing rains during curing/drying in the field remains high. Such rains may cause a serious damage to the crop and pod losses may range up to 50 percent. Pods become blackened and attacked by the mould and lose the market value. In the All India Coordinated Research Project (ICAR) on “Harvest and Post Harvest Technology Scheme” at Gujarat Agriculture University the following harvest and post-harvest losses in groundnut have been assessed (Table 22).groundnuts losses

Table 22. Harvest and post-harvest pod losses in groundnut in Gujarat, India.

Source: Singh and Memon, 1983.groundnuts losses

In Sudan groundnut is cultivated in heavy clay soil, the particles of the soil adhere to the pods causing problems during harvesting. It is also observed that extra shaking reduced combining losses by decreasing pre-combine and header losses. One extra shaking could reduce total combining losses by up to 3 percent.