write two major disease each of pulses and oil seed crops..
Answers
It is a form of multiple cropping in which crops are grown in sequence on the same field, with the succeeding crop planted after harvest of the preceding crop. This system with relatively short growing season crops offers better total annual use of land than a single crop system. The prominent sequential cropping systems involving different pulses have been discussed crop wise.
Rice-Chickpea/ Lentil/ Field pea
With the development of wheat varieties amenable for late-planting up to late December and January, the area under rice-wheat system has increased at a faster rate in the last two decades. The adverse effect of this system on soil health is being widely recognized.
In recent years, development of early maturing varieties of chickpea suitable for planting up to mid of December with yield potential of 15-20 q/ha has enabled farmers to adopt rice-chickpea system instead of cereal-cereal system especially in the tail end of command areas in eastern U.P. and Bihar. Similarly on the upland of Punjab, Haryana and western U.P., where cotton is grown as commercial crop, chickpea can be successfully introduced. Under resource constraint particularly irrigation water, chickpea is more remunerative than wheat. In low land areas of eastern region, lentil proved to be better one over chickpea. The major constraints in fast spread of this system are limited choice of improved varieties and incidence of pod borer, Botrytis gray mold, Ascochyta blight besides poor soil tilth and nodulation.
Pigeonpea - Wheat
Pigeonpea is a major crop of Maharashtra, Uttar Pradesh, Madhya Pradesh, Karnataka and Gujarat. In the irrigated areas of the northern and central India, pigeonpea-wheat has emerged as a promising system. Availability of short duration varieties such as UPAS 120, Manak, ICPL 151, Pusa 992, which takes about 120-160 days to mature has enabled their introduction in rice wheat systems in irrigated area of western U.P., Punjab and Haryana, Delhi and North-East Rajasthan. This has provided desired stability and sustainability to productivity of cereal based cropping system. But there are some issues, which need to be tackled for wider adoptability and profitability from this system. Presently, most of the short duration varieties of pigeonpea available for cultivation are affected by sterility mosaic, Fusarium wilt and Phytophthora blight and have tendency to prolong maturity with the late monsoon. Therefore, development of varieties, which could mature by early November with 2 t yield/ha is required.
Rice - Urdbean/Mungbean/ Lathyrus
Cultivation of rabi urdbean and mungbean in coastal regions of South India is being practiced since long but it could get momentum only after development of powdery mildew resistant genotypes such as LBG 17, LBG 402, LBG 611 and LBG 22 having high yield potential. Development of these varieties in late eighties has revolutionized urdbean and mungbean cultivation in rice fallow especially in Andhra Pradesh. This system is highly productive and stable besides its benefits through improvement in soil health. This cropping system is now being practiced in other states like Odisha, Tamil Nadu and Karnataka.
Other systems
Mungbean/urdbean – mustard/barley is an important crop sequence in rainfed. areas of north-western region of India like Punjab, Haryana, Western Uttar Pradesh, Rajasthan, Himachal Pradesh and Jammu & Kashmir whereas in irrigated areas, maize-potato-mustard-mungbean/urdbean and maize–wheat-mungbean/urdbean practices are followed. Similarly in the eastern Uttar Pradesh, Bihar, West Bengal, Orissa and Assam, maize-horsegram rotation is followed under rainfed conditions and maize-wheat-mungbean /urdbean under irrigated condition. In the central regions of India comprising Madhya Pradesh, Gujarat and Maharashtra, urdbean wheat, mungbean-sorghum, cowpea/urdbean/mungbean-safflower and mungbean-niger are some of the important cropping sequences under rainfed conditions but under irrigated condition, maize-wheat-summer cowpea, maize wheat-summer urdbean/mungbean are practiced. In the rainfed area of South India including Andhra Pradesh, Tamil Nadu, Karnataka and Kerala, cowpea-finger millets, mungbean-sorghum/safflower, rice-mungbean/urdbean/cowpea are followed while under irrigated conditions, rice-rice-mungbean/urdbean/cowpea are common.
Two diseases of pulses are wilt and rust.
Two diseases of oil seed crops are Rhizopus head rot and rust.
EXPLANATION:
Wilt is a disease that is soil and seed borne. The seedlings of such pulses die and the color of the plant turns yellow and light brown. Rust is a disease in which yellow spots are found in clusters on the leaves. The leaves develop pustules and turn dark brown.
In head rot, brown and irregular spots develop on the crop. In rust, brown or orange to black pustules appear on the lower leaves of the crops. The leaves also turn dry prematurely.