Bhuvan Jung Pudashini(Agriculture Expert)
Grain legumes plays important role in cropping systems in Nepal. They occupy more than 319472 ha (13% of food crop producing land area) and produce a total of 262356 t grains. With the rise in income levels and change in consumption pattern in recent Nepal, the domestic demand of food legumes would have risen up to 329 and 450 thousand metric tons by the year 2010 and 2020, respectively. Major legumes include soybean, black gram, horse gram, cowpea, mung bean, and groundnut lentil, khesari, chickpea, and faba bean. Pigeon pea (Cajanus Cajan (L.) Based on the demands projection of food legumes in Nepal, Nepal needs to increase the area by 0.4%, production by 4.7% and productivity by 4.2% annually (Yadav, 2009) but the trends in grain legumes area, production and yield in Nepal.
| Advertisement |
However, the rise in the cost of fertilizers, their unavailability at the right time and low purchasing power of the farmers coupled with the slow growth of irrigation facilities have limited the potential productivity of rice-wheat cropping in Nepal.
Diseases and insect pests are the two most important biotic constraints to the production of legumes in Nepal which cause considerable yield loss. In legume crops, important pathogens such as several viruses, fungi and the bacteria have been reported. Most taxonomic group of plant viruses are reported to occur or infect in legumes and at least 279 different legume species are naturally infected by 171 viruses (Brain et. al, 2010).Soybean mosaic virus(SMV) and Tobacco ringspot virus(TRSV) in soybean, Bean common mosaic virus(BCMV) in bean(Phaseolus vulgaris),Mungbean yellow mosaic virus(MYMV)sterility mosaic in pigeon pea, Cowpea aphid-borne mosaic virus(CCAMV) in cowpea, Southern bean mosaic virus in yard-long bean and Pea seed borne virus(PSbMV)in pea have been reported in Nepal. Likewise, several fungal diseases have been reported in various legume crops. Anthracnose, pod and stem blight, gray mold and leaf spot are the major economic importance diseases on legume in Nepal.
A large numbers of diseases have been reported in legume crops only on field symptom in Nepal. Only the study confirms the first report of infection of BCMNV in sweet bean cultivated in Malepatan research centre in Nepal and MYMIV in kidney bean and lima bean by molecular means(PCR). There is also number of the other virus infecting legumes, thus, pandemic COVID-19 had also given the knowledge of viral diseases so they must be further studied to know the occurrence of viral diseases in Nepal by nation as soon as possible before it cause the disaster in plant science. So, for the control strategy the farmer should use the healthy seed. Resistance varieties are also released in developed country but for the undeveloped country it may not be possible to import these verities. At least they can follow some precaution like rotation cropping, avoidance of weed (carrier of virus), avoidance of seed infected by virus, as far as possible to use the seed from seed company.