Farmers’ management of peanut (Arachis hypogaea L.) diversity, their varietal preference traits and uses in Southern and Central Benin

Background Peanut ( Arachis hypogaea L.) is one of the major oilseed legumes contributing to food security and poverty reduction in Benin. Unfortunately, several constraints hamper peanut production in Benin leading to a low yield. Knowing that seed is crucial for increase agricultural productivity, a good knowledge of on-farm management of grown peanut diversity and uses that allow its maintenance in traditional Beninese agriculture are prerequisites to establish an efficient breeding and conservation programs. Therefore, this study aim to document peanut varietal diversity, folk nomenclature, seed system, storage constraints, seeds pest management practices, varietal preference criteria, cultural taboos and uses in southern and central Benin. Methods Two hundred and sixteen (216) farmers were surveyed through 32 villages in southern and central Benin using research tools and techniques of rural appraisal such as field visits, group surveys and individual surveys using a questionnaire. Results Fifty-four peanut folk varieties grouped into 8 morphotypes based on the seed characteristics were registered in the study area. All local names given to peanut folk varieties by ethnic groups have meaning. The number of folk varieties maintained per village ranged from 1 to 11 (an average of 4) and varied between 1 and 4 per household. Some peanut producers reported the disappearance of some folk varieties. The drop in yield was the main reason of peanut varietal disappearance in the study area. Rodent attacks were the most important constraints of peanut production in the study area. Varietal preference criteria varied from ethnic groups with seed size and many pod/seeds per plant as the main preferred traits. Peanut seed system was mainly informal. For peanut seed conservation, farmers use various storage tools. To alleviate pest problems in stored peanut, producers used plant biocides and synthetic chemicals. Some cultural taboos and various uses (food, feed and medicinal) of peanuts have been recorded in the southern and central Benin. Conclusions Our results suggest that for boost peanut production in central and southern Benin, breeders must create high yielding peanut varieties. For the adoption of these new varieties, it is important to take in account the preference varietal criteria of each ethnic group. To a good estimation of peanut diversity in the study area, morphological and molecular characterizations were recommended.

Field screening of common jute (Corchorus olitorius) varieties against major pests in Eastern Terai region of Nepal

Field screening of eleven most popular jute varieties belonging to Corchorus olitorius species was done against the major pests in the farm of Jute Research Programm, Itahari, Sunsari, Nepal during 2017 and 2018. Different species of pests belonging to insects, mites and nematodes were found feeding on jute. Among them, jute Semilooper (Anomis sabulifera Guen.), Bihar hairy caterpillar (Spilarctia obliqua Wlk.), yellow mite (Polyphagotarson emuslatus Banks), are causing economic damage to the jute crop. Eleven jute varieties were selected to conduct varietal preference and tested against major pest of jute in field condition. Among the eleven varieties JRO-524 was found to be moderately resistant against the Semilooper (A. sabulifera) and Bihar hairy caterpillar (S. oblique) but least susceptible to yellow mites. Likewise, the variety KEN-DS-058, KEN-DS-066, BJRI-1965 and BJRI-1968 showed highly susceptible to major pest Semilooper (A. sabulifera), Bihar hairy caterpillar (S. oblique) and yellow mites. The variety BRD-SRB-061, YA-41, O-4, KEN-BL-130, Itahari-2 showed moderate resistance to Semilooper (A. sabulifera), Bihar hairy caterpillar (S. oblique) but moderately susceptible to yellow mites. Further, the fibre production capacity of the varieties under different pest’s pressure was found relatively higher in variety JRO-524 followed by YA-41, BRD-SRB-061, KEN-BL-130 and O-4 respectively. The relatively higher yield recorded under varying pest levels over two consecutive seasons is an indicative of greater field tolerance of olitorius jute varieties.

Study on varietal preferences and seasonal incidence of parasitoids of rice pests

The egg masses of yellow stem borer, larvae of leaf folder and rice horned caterpillar and eggs of ear head bug were collected randomly at fortnightly interval from four different varieties viz., CO 43, CO 50, CO 51 and CR 1009 from the rice field. The data was pooled and per cent parasitization was calculated to find out the varietal preference and seasonal variations of parasitoids. Among the four different varieties tested for the preference of parasitoids, per cent parasitization of stem borer egg mass was found to be more (26.59) in CO 50. The per cent parasitization of leaf folder larvae and rice horned caterpillar was found to be maximum in CO 51(40.29) and CO 43(33.21), respectively. In case of ear head bugs, the egg parasitization was maximum (27.70) in CO 50. The mean egg mass parasitization of stem borer was highest (71.88) in first fortnight of December. The larval parasitization of leaf folder and rice horned caterpillar were found to be maximum during the second fortnight of December (64.3) and the first fortnight of January (71.88), respectively. The parasitism rate of ear head bug eggs was maximum (62.95) during the second fortnight of December. Interestingly, phoresy exhibited by Sceliocerdo sp. an egg parasitoid of Neorthacris sp. was also recorded.