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南阳盆地是我省重点棉区之一,常年种棉170万亩左右。近年来,随着农业生产的发展,耕地的复种指数和单位面积产量不断提高,氮、磷化肥的施用量日益增多,而有机肥的施入量则逐年减少,致使不少棉田营养元素比例失调。缺素性酶棉红叶茎枯病发生严重,并呈逐渐扩展蔓延的趋势。1987年我区发病面积占总种植面积的15～20%。其中南阳县发病30万亩左右,占该县植棉面积的
Nanyang Basin is one of the key cotton areas in our province, with annual planting of about 1.7 million mu of cotton. In recent years, with the development of agricultural production, the index of multiplication of cultivated land and the yield per unit area have been continuously increased, the application amount of nitrogen and phosphorus fertilizers has increased day by day while that of organic manure decreased year by year, resulting in the imbalance of nutrient elements in many cotton fields . The lack of enzyme cotton leaves stem blight serious, and gradually spread the trend of expansion. In 1987, the area of disease in our region accounted for 15 ~ 20% of the total planted area. Including Nanyang County incidence of about 30 acres, accounting for the county cotton area