万亩香蕉基地和技术协会的奇迹

一笔经济账1985年,广东省潮阳市灶浦镇掀起了一股抢种香蕉的热潮,一下就扩大到1000农户,共种植香蕉4500亩,为什么?世世代代在这片沃土上面朝地、背朝天种植水稻的农民,算了一笔经济账:种植水稻,年亩产2000斤,收入1600元;而种植香蕉年亩产3000斤,收入4500元,价差为2900元。天呀,近3倍的收入哪里去找?农民觉醒了。改变经济结构、改造产业结构。

南宁主要香蕉种植基地土壤肥力调查与施肥建议

香蕉具有速生高产,需肥量大的特性。营养充足、健康的土壤可以促进其生长及产量的提高。因此对香蕉土壤肥力状况进行调查与评估,对于指导当地农民进行合理施肥,提升土壤肥力和提高香蕉产量及经济效益具有重要的意义。结果表明:88.88%的南宁地区香蕉种植基地土壤pH低于5.5; 40.74%的香蕉种植基地土壤有机质含量低于20g/kg;南宁主要香蕉种植基地土壤的铵态氮和硝态氮平均值分别为22.04和15.44 mg/kg,大多数南宁香蕉基地铵态氮含量高于硝态氮的含量,铵硝比不佳; 55.56%的香蕉种植基地土壤有效磷低于10 mg/kg;66.65%的基地土壤速效钾含量高于100 mg/kg; 70.37%的香蕉种植基地土壤交换性钙高于250 mg/kg; 62.97%的基地土壤交换性镁含量低于25 mg/kg。因此,为了提高南宁地区香蕉基地土壤肥力利用效果,实现香蕉产业可持续发展,提出了合理的施肥建议:适当施用石灰或碱性肥来改良土壤酸性,提高土壤pH,增施有机肥改善土壤肥力结构;氮肥以施用硝态氮肥为主,配合适当比例的铵态氮肥,增施磷肥、镁肥,合理施用钾肥,部分地区增施钙肥。

Studies on the cloning genomec5 of BBTV in Guangzhou areas and its expression in transgenic banana

The DNA was isolated from banana bunchy top virus （BBTV） in Guangzhou areas and a l.lkb DNA of replicas of BBTV was obtained by PCR using this virus DNA as templates for amplification. This reformed DNA of the BBTV replicas which being homologous to 90% with the Australia＇s encoded the C-Terminal of BBTV replicas. The reformed BBTV replicas were cloned to pBI121 in the position between CaMV 35S promoter and NOS termination sequence, and a plant-expressed carder was established. Four transgenic bananas with the expression of BBTV replicase gene in To generation were detected with PCR and Western blot analysis. The ability of these transgenic bananas against bunchy top virus is being analyzed.