Comprehensive Control Methods and Technical Key Points for Cowpea Viral Disease
Cowpea (scientific name Vigna unguiculata), commonly known as yardlong bean, ginger bean, banded bean, hanging bean pod. Cowpea is divided into two types, long cowpea and rice cowpea, and belongs to the legume family. Cowpea is an annual plant of the legume family. The stem has three types: dwarf, semi-vining and vining. In southern cultivation, vining types are predominant, followed by dwarf types.
Morphological characteristics of cowpea
Annual twining, herbaceous vine or nearly erect herb, sometimes twining at the tip. Stem nearly hairless. Pinnately compound leaves with 3 leaflets; stipules lanceolate, about 1 cm long, extending downward at the point of attachment into a short spur, with linear markings; leaflets ovate-rhombic, 5-15 cm long, 4-6 cm wide, apex acute, margins entire or nearly entire, sometimes pale purple, hairless. Racemes axillary, with long peduncles; 2-6 flowers clustered at the tip of the inflorescence, with fleshy glands often between the pedicels; calyx pale green, bell-shaped, 6-10 mm long, lobes lanceolate; corolla yellow-white with a slight greenish-purple tinge, about 2 cm long, all petals with claw, standard petal oblate, about 2 cm wide, apex slightly emarginate, base slightly auriculate, wing petals slightly triangular, keel petals slightly curved; ovary linear, hairy.
Pods pendulous, erect or spreading obliquely, linear, 7.5-70 (90) cm long, 6-10 mm wide, slightly fleshy and inflated or firm, with many seeds; seeds oblong-elliptic or cylindrical or slightly kidney-shaped, 6-12 mm long, yellow-white, dark red or other colors. Flowering period May-August. Leaves are trifoliolate compound leaves, with 20-25 cm long peduncles emerging from the leaf axils, bearing 2-4 pairs of flowers at the tip, white, red, pale purple or yellow, generally bearing only two pods, pods slender, varying by variety, about 30-70 cm long, with colors such as dark green, pale green, red-purple or reddish mottling. Each pod contains 16-22 seeds, kidney-shaped, with red, black, reddish-brown, red-white and black-white bicolor seeds, etc. The root system is well developed, with pink root nodules on the roots.
Comprehensive control of cowpea viral disease
Symptoms and transmission routes of cowpea viral disease:
The disease presents systemic symptoms, with dark green and light green mosaic on the leaves, sometimes chlorophyll aggregation visible, forming dark green vein bands and symptoms such as shrinking and leaf curling. It is mainly caused by infection with Cucumber mosaic virus (CMV), Cowpea aphid-borne mosaic virus (CoAMV) and Broad bean wilt virus (BBWV). The three viruses are mainly transmitted non-persistently in the field by various aphids such as green peach aphid and cowpea aphid, and can also be transmitted by sap rubbing inoculation of diseased plants and agricultural operations.
Comprehensive control methods for cowpea viral disease:
① Select disease-tolerant varieties such as Zhijiang 28-2 and Hongzuiyan.
② Control aphids early.
③ Strengthen management and improve disease resistance.
④ In the early stage of the disease, spray 1.5% Zhibingling II emulsifiable concentrate at 1000 times dilution, or 83 Zeng Kang Ji at 100 times dilution, or 20% Kangbingsheng emulsifiable oil at 500-800 times dilution, or 60% Virus A tablets (add 2 tablets to 15 kg water), or 20% Wanduqing at 500 times dilution, or 20% Virus A wettable powder at 500-700 times dilution, or 6% Bingduke or 20% Bingdubike wettable powder at 1000 times dilution, or 38% Virus No. 1 at 600-800 times dilution, or compound Kebingshen at 500 times dilution plus Zhibaosu at 500 times dilution, or Bingduwang at 500 times dilution plus balancing agent at 300 times dilution, or Bingdu Sukeling emulsifiable oil at 500 times dilution plus KangHanzengchan agent (zinc fulvate) at 500 times dilution, spraying once every 7-8 days, for 3-4 consecutive sprays.