二氧化硫及氮氧化物對農作物為害病徵及產量影響

Abstract

分別放置盆栽農作物（水稻、玉米、落花生及番石榴）於作物同化箱內，控制氣溫、相對濕度、風速及二氧化碳濃度，並於自然陽光下（時間為10:00至14:00）使植物進行飽和光合率條件下，利用密閉循環方式，分別燻蒸SO2,NOx及HF等空氣污染氣體，五天後，作物未呈現症狀。燻氣二週後，葉片呈現各現病徵：如水稻呈現褐色條斑，玉米灰白色條斑，落花生褐斑，番石榴紅褐斑等。較後期病徵則：玉米矮小，水稻葉片枯萎多抽穗少，落花生花器凋萎，番石榴葉片嚴重捲曲等生長及發育遭受破壞，導致產量減少。按氣體影響之大小程度，係依5 SO2(O.5 ppm)+NO2(O.1 ppm)、SO2(O.5 ppm)、SO2(O.1 ppm)+NO2(O.1 ppm)+HF(0.01 ppm)、SO2(O.1 ppm)+(NO2(O.1 ppm)、SO2(O.1 ppm)及NO2(0.01 ppm)順序而遞減。同時燻氣SO2，收穫作物葉片含硫量增加。可能由於SO2經葉片氣孔進入細胞內，造成生理代謝方面之不平衡，而使植物細胞組織受損，若嚴重時，呈現特別病徵。 The potted agronomic crops rice, corn, peanut and guava in assimilation chamber under the saturated photosynthetic condition were fumigated with SO2, NO and HF gases. The fumigating period was from 10:00 to 14:00. After two weeks, the fumigated crops appeared symptoms such as brown mottlings of rice leaf, grey-white mottlings of corn leaf, brown spots of peanu leaf, and red brown mottlings of guava leaf. The more severe damage for the later stage of growth and development were the shorter stem of corn, small tillers of rice, premature fade of peant flower, and the curved leaf of guava. All of the morphological symptoms resulted in the yield reduction. The damage degree of the fumigating gases were according to the following order to be reduced : SO2(0.5 ppm) + NO2(0.1 ppm), SO2(0.5 ppm), SO2(0.1ppm) + NO2(0.1 ppm) + HF(0.01 ppm), SO2(0.1 ppm) + NO2(O.1 ppm), SO2(0.1 ppm) and NO2(0.1ppm). In addition, the leaf sulfur content of the S02-fumigated crops was increased.