Benefits and techniques of multiple cropping of Rice and Zizania latifolia

Chongxian Town, Yuhang District, Hangzhou City is located in the plain water network zone, originally mainly to grow rice, but also some Zizania caduciflora, Pleurotus ostreatus, lotus root and other aquatic crops. In agricultural development and industrial structure adjustment, Chongxian Town made use of local soil and water resources, vigorously expanded the area of rice-Zizania caduciflora multiple cropping, and took Zizania caduciflora production as an efficient agriculture of the vegetable basket project. The district, town and village invested 2 million yuan to establish the Chongxian Village Zizania caduciflora demonstration Park. In 2005, Hangzhou Agricultural Comprehensive Development Office established it as the national agricultural comprehensive development high and new technology demonstration project (aquatic vegetable demonstration zone). In 2006, it was designated as the pollution-free Zizania caduciflora base in Zhejiang Province. The town government also invested 1 million yuan to establish a trading market for Zizania caduciflora, and invested more than 1.5 million yuan to build a cold storage for storing Zizania caduciflora, which provided favorable conditions for stabilizing grain, developing Zizania caduciflora, increasing efficiency and increasing income.

1. Multiple cropping model and benefit analysis

The cultivation area of rice-Zizania caduciflora multiple cropping in Chongxian town has reached more than 6500 mu (1 mu = 667m2, the same below). It mainly adopts two models: "early rice-Zizania latifolia" and "Zizania caduciflora-late rice". The former is planting Zizania caduciflora after harvest of early rice, and the latter is planting late rice after harvest of Zizania latifolia in summer, which is a two-year rotation system.

Practice has proved that multiple cropping of rice and Zizania caduciflora creates high yield and high benefit. In Chongxian town, the yield per mu of 8000 mu of early rice is more than 400kg for three consecutive years, and the yield of 7000 mu of late rice is more than 550kg per mu, and the yield of grain per mu can be 50 kg higher than that of simply growing rice. Planting rice in Zizania latifolia field can also reduce fertilizer use and save cost. In 2006, more than 6500 mu of Zizania latifolia in Chongxian Town produced an average yield of 3500 kg per mu (retaining 2 short leaf sheaths), including 2400 kg in summer and 1100 kg in autumn. Calculated according to the average price of 1.40yuan per kilogram in two seasons, the output value per mu is 4900 yuan, deducting the cost 750yuan per mu, the net profit is 4150 yuan.

two。 Cultivation techniques of high yield and high efficiency

For rice cultivation, early rice mainly uses Hang 959 varieties, and the management is carried out according to the routine, with emphasis on field shelving and control of sheath blight. The late rice variety Jiahua No. 1 is mainly used, and the cultivation and management is generally carried out according to the routine, with emphasis on: crushing and raking after digging up the old pier of Zizania caduciflora, cultivating strong seedlings, proper sparse planting, careful topdressing, setting up the field and so on. Now only the cultivation techniques of Zizania caduciflora are introduced as follows.

The main results are as follows: (1) the selection of excellent varieties of Zizania caduciflora should have the characteristics of high yield and high quality and the ripening period to meet the market demand. We selected double-season Zizania caduciflora varieties, of which the mid-and late-maturing Zizania latifolia No. 2 white shell Zhuzi species accounted for 60%, purple shell Zhuzi species accounted for 35%, and early-maturing cotton strips accounted for 5%.

(2) Seedling technique

1) selection of mother pier. In the early stage of harvest of Zizania latifolia in autumn (early and middle October), the seeds of Zizania caduciflora with early, uniform and white and tender hypertrophy were selected and marked, and re-selected before and after Ching Ming Festival in the following year. Zizania caduciflora with uniform tillers and uniform leaf height were used as seedlings.

2) Seedling period and density. Raise seedlings from Qingming Festival to Grain Rain, dig up the "seed pier" and plant it. Before planting, cut off the upper leaves of the seedling and leave 30 cm at the base to reduce water evaporation and improve the survival rate.

3) weeding, fertilizing and shelving the field in time, dry and wet to promote growth.

4) Control of diseases and insect pests. The plant is tender green at seedling stage, and it is easy to be damaged by rice thrips, aphids and borer, so the control methods refer to rice pest control, and the comprehensive control method of stripping old leaves and diseased leaves is adopted in seedling stage.

(3) Field planting

1) Field selection. The selection of rotation rice fields with convenient drainage and irrigation and fertile soil is beneficial to improve the soil, reduce the occurrence of "Zizania latifolia" and reduce the damage of diseases and insect pests.

2) soil preparation. The field was ploughed and leveled before transplanting, and 50 kg of ammonium bicarbonate per mu was applied as base fertilizer one day in advance.

3) planting period, method and density. In late July, the seedlings of Zizania caduciflora were dug up and split, the upper leaves were removed, the length of the seedlings was 30 cm, the distance between plants and rows was 80 cm × 75 cm, and 2 seedlings were planted in each hole, and the seedlings were protected by inch water after planting.

(4) fertilization technology

1) raising seedlings and fertilizing. 7-10 days after planting in autumn, 1000 kg of human feces and urine, or 50 kg of ammonium bicarbonate per mu should be applied, and the remaining leaves of overwintering Zizania caduciflora should be cut off and fully applied organic fertilizer in the first and middle of February. 2000 kg of cow manure or 1000 kg of chicken and duck manure can be used to facilitate the development and growth of buds.

2) Tillering and thickening. At the early stage of tillering, 1000 kg of human feces and urine or 50 kg of compound fertilizer were applied per mu. Zizania latifolia was applied in mid-August in autumn and in mid-and late March in summer.

3) pregnant Zizania caduciflora. In the late tillering stage, that is, in mid-September in autumn and in mid-April in summer, ammonium bicarbonate of 50-75 kg per mu was applied, depending on the increase or decrease of soil fertility. During the period of fertilization, the water layer of 6cm to 7cm is maintained on the field surface to prevent the root injury or loss of fertilizer.

(5) Water slurry management according to the growth and season of seedlings, transplanting to the peak tillering stage in autumn, overwintering old Zizania latifolia to summer tillering peak stage, irrigation with shallow water 3cm, which is beneficial to early root tillering and anti-freezing in winter; among them, autumn Zizania latifolia needs to be drained and dried for 2-3 days in the middle of August, gently laid once to promote rooting and tillering; Zizania latifolia maintains a water depth of about 15 cm during pregnancy to inhibit ineffective tillers and ensure that Zizania caduciflora is tender.

(6) Seedling thinning and weeding before and after the Qingming Festival, for the overdense Zizania caduciflora pier, press a small piece of mud in the middle of the Zizania caduciflora pier, in order to reduce some small tillers and thinning seedlings, in order to facilitate pregnancy. At the same time, pull out the weeds in the field in time, peel off the yellow leaves and diseased leaves at the base of Zizania caduciflora seedlings.

(7) the common diseases of Zizania latifolia are flax spot, rust, sheath blight and so on. Sesame spot disease can be sprayed with 40% chlorphenicol 600x, or 50% carbendazim wettable powder 8000x, or 1.5% triadimefon wettable powder 1000 times, or 25% enemy emulsifiable concentrate 3000 times spray; sheath blight can be sprayed with 1000 times of Jinggangmycin water, required to be sprayed on the leaves, fine spray, wet leaves for the degree, so as not to affect pregnancy. The main pests are Chilo suppressalis, Chilo suppressalis, thrips, aphids and leafhoppers. The control method refers to rice pest control, we can choose 20% triazophos EC 600x solution, or 40% dimethoate 1000 times solution and other spray, Zizania caduciflora pesticide is prohibited during pregnancy.

(8) the standard of timely harvest of Zizania caduciflora is as follows: the pillow of three outer leaves is flush, the base of Zizania caduciflora is significantly enlarged, and the skin of Zizania caduciflora is clean. It is usually harvested every 2-3 days to prevent the skin of Zizania caduciflora from turning green and aging.