不同激素处理对锦橙果实留树贮藏的效应研究

2002—2004连续2个年度开展了锦橙果实留树贮藏试验，研究了果实转色前2个月（8月中旬）至果实自然成熟期后的1个月（1月中旬）期间2，4-D与增施氮肥、覆盖地膜、喷布赤霉酸（GA，）和6-苄基腺嘌呤（6-BA）的单独或复合处理的效应。结果表明，与对照相比，各处理均能明显延迟果实成熟和减少果实脱落，其中以增施3次尿素＋喷布1次10mg／LGA3＋喷布4次20—40mg／L2，4-D处理效果最佳，留树贮藏到自然成熟期3个月后累计落果率约15％；果实转色前喷布GA3或土施尿素能延迟果实上色1～2个月，2者合用有增效作用。喷布2，4-D可有效减少留树贮藏果实的脱落，而增施氮肥、覆盖地膜、喷布GA，和6-BA对防止果实脱落的作用不大。各处理对次年春梢长度和叶片数无显著影响，但少量处理对春梢粗度的影响达到显著差异。在留树贮藏期间，果实可溶性固形物含量上升0．9～2．0个百分点，含酸量降低0．37～0．55个百分点，固酸比提高9．58～13．00。

EFFECTS OF DIFFERENT HORMONE TREATMENTS ON "ON -TREE STORAGE" OF JINCHEN ORANGE FRUIT

Urea app lication,p lastic film mu lch ing,GA3,6-BA or 2,4-D spray were used alone or in comb ination in fru it on-tree storage experim entw ith Jinchen orange(C itrus sinensisOsbeck) in the two seasons of 2002 /2003 and 2003 /2004.A ll the treatm ent a-dopted delayed fru it color developm ent and decreased fru it drop.Best resu lt was ach ieved in the treatm ent of thrice urea app lication + once 10 mg /L GA3sprays + four tim es 20 ~40 mg /L 2,4-D spray,w ith a total accumu lative fru it drop rate of 15% 3 months after fru it naturalm aturation.GA3spray or urea app lication in December and October delayed fru it color developm ent by 1 ~2 months,and the com-b ination of the two gave better resu lts than the single treatm ent.Spray of 2,4-D had a sign ificant effect in decreasing fru it drop,wh ile the effect of urea app lication,p lastic film mu lch ing orGA3or 6-BA spray showed little effect on fru it drop.The treatm ent had no sign ifi-cant effect on the leaf number and the length of spring shoots developed the next year but a few treatm ents had som e effect on the ir th ick-ness.During storage of fru it on the trees,its total solub le solids(TSS) rose by 0.9 ~2.0 and its total ac id content decreased by 0.37% ~0.55%,resu lting in an increase in TSS /ac id ratio by 9.58 ~13.00.