Deng YunCun;Deng XiaoPing

;Yongzhou Agricultural Science Research Institute, Yongzhou 425000, China.

crop quality;crop yield;cultural control;dormancy;drought;fruits;grapes;maturation;mulches;mulching;plant ecology;rice;rice straw;soil organic matter;soil temperature;soil water;straw;tillage;weed control;weeds

A study was conducted at a fast-growing and high-yielding vineyard in Caishi town, Lengshuitan district, Yongzhou, Hunan, China during 2001-04. Grapevines were transplanted in February 2001 at a density of 1.0x2.2 m with population of 300 plants/667 m2, selecting incessant 8 rows of grape plants with 31 plants in each row as the test plot. Five incessant grape plants were grown without mulching in every row, and all the other plants with mulching. The first mulching was carried out in June before the end of rainy season, i.e. the time of first inter-tillage, mulching the surface of ridge with 20 cm-thick fresh rice straw; to non-mulched plants, only an inter-tillage was performed. In October, with the rotted rice straw on the surface of the ridge, the second inter-tillage and mulching were carried out. The results indicated that in Yongzhou with severe drought condition in July and August and in shortage of irrigation, favourable mulching in proper time conserved more moisture in soil, alleviated adverse effect of drought, and secured high grape yield and quality. Mulching in summer lowered soil temperature, alleviated the dormancy resulted from high temperature, and guaranteed the maturity of grape fruits. In winter, mulching relatively increased soil temperature and delayed the time of dormancy resulted from low temperature. Mulching increased soil organic matter content, and kept loose and mellow soil favourable for root development. Mulching also decreased weed biomass compared with no mulching..