赣南脐橙叶片黄化及施硼效应研究

采用田间试验，设施硼(Na2B4O7.10H2O 15 g/plant)和不施硼2个处理，探讨赣南纽荷尔脐橙的叶片黄化、落果及其施用硼肥的效应。结果表明，施硼明显改善了脐橙的生长发育和硼营养状况，和不施硼的对照比较，叶片数增加39.8%，老叶黄化叶片数由12.9%下降到3.2%；单株结果数和单果重分别增加10.5%和11.9%，增产达23.3%，经济效益较好。脐橙在果实膨大期需硼量占90%以上，施硼后脐橙植株硼、镁含量和硼吸收量显著提高，并且植株各器官的硼分配比例得到改善。

Effect of boron on the leaves etiolation and fruit fallen of Newhall Navel Orange

It is the citrus predominance district programming of Southern Jiangxi promulgated recently by Ministry of Agriculture. The citrus area is about 100000 ha in this region, and most of the orchards are on hilly and mountainous land where purplish red sandstone of Tertiary period is extensively distributed. The research had been carried out through field experiment since 2006, and mainly studied the effect of boron fertilizer on the yellow leaves and fallen fruit of Newhall Navel Orange（Citrus sinensis Osbeck Newhall）in Southern Jiangxi. Which installed two B levels (CK, 0 mg/kg and +B, Na₂B₄O₇.10H₂O 15 g/plant), each level had three repetitions. The result showed that boron applying was obvious improvement the growth of the navel orange and boron nourishment condition, the number of fruit per plant average increase 39.8% compared no boron fertilizer, and the number of old yellow leaves reduced from 12.9% to 3.2 %; Weight and number of fruit both increased, the weight of single fruit increase 11.9%, and the fruit yield of per plant increase 10.5 %. Totally, the fruit yield will increase about 23.3% per hectare, which can bring high economic profit to fruit grower，there will be need 90% boron for orange growing at fruit expanding stage. Boron content and accumulation of each fruit organ significantly increased, and boron distribution also more proper in plant different organ. Therefore, boron applying could allay leaves etiolation and fruit fallen of Newhall Navel Orange, so increase fruit yield.