Researches Of Chemicals Inhibiting Germination Of Onion Bulbs And Their Physiological Mechanism

Onion bulbs were treated with six kinds of chemicals (hydrochloric acid,sodium hydroxide, maleic hydrazide, sorbic acid, salicylic acid, ethylene)in three concentration respectively , at the time of 2 weeks in front harvest and after harvest by spraying and dipping .The results showed that there were significant inhibiting effect on the onion bulbs germination rate by spraying with five kinds of chemicals .The germination rate by spraying with HCl1400ppm,NaOH450ppm,MH1600ppm, SA1000ppm and Eth200ppm was 20%,10%,14.08%,7.65%,20% lower than that of CK respectively. The difference was significant or most significant. The inhibiting order was Eth200ppm>HCl1400ppm>MH1600ppm>NaOH450ppm>SA1000ppm. There were significant inhibiting effect on the onion bulbs germination rate by dipping with six kinds of chemicals . The germination rate by dipping with HCl2100ppm,NaOH300ppm,MH2000ppm,SBA2000ppm,SA800ppm and Eth200ppm was 15%,15%,15%,21.66%,15%,18.33% lower than that of CK .The difference was significant or most significant. The inhibiting order was SBA2000ppm>ETH200ppm>HCl2100ppm>MH2000ppm>NaOH300ppm>SA800ppm. The measure of four physiological-biochemical indexes of treated onion bulbs showed that there were positive interrelationships between soluble sugar content, total amylase activity and germination rate of onion bulbs ; there was negative interrelationship between IAA oxidase activity and germination rate of onion bulbs; there was not interrelationship between soluble protein content and germination rate of onion bulbs.