农民增收的政策与制度探讨

从理论上讲 ,农民增收是一个社会分配问题 ,但从其实质上是一个政策和制度问题。因为制度和政策导向规定了在一定历史时期内的利益分配趋向。因此 ,研究农民增收问题 ,必须从政策和制度的角度加以分析。拟从政策和制度等方面对农民增收问题作一些探讨 ,从而为增加农民收入提供一些有益的建议     

独占春种子非共生萌发和低温离体保存

独占春(Cymbidium eburneum Lindley)成熟种子无菌播种诱导原球茎,并以原球茎进行低温离体保存。结果表明:在培养基花宝1号3g/L LH(水解乳蛋白)1g/L BA(细胞分裂素)0.5 mg/L NAA(生长素)0.1 mg/L CM (椰子汁)100 ml/L AC 2 g/L 蔗糖25 g/L中种子萌发出原球茎;原球茎在培养基1/2 MS LH 0.5 g/L BA 0.5 mg/L NAA 0.1mg/L AC 2g/L 蔗糖20g/L中于6℃黑暗条件下连续保存了20个月,成活率达85%,并能在恢复培养基MS BA 3～5 mg/L NAA 0.2 mg/L AC 1g/L CM 100 ml/L 蔗糖25 g/L中进行恢复增殖培养。     

Gulf stream and middle atlantic bight: complex thermal structure as seen from an environmental satellite

High-resolution infrared imagery from the ITOS 1 satellite demonstrates the utility of synoptic sea-surface temperature information. The northern edge of the Gulf Stream, the slope waters, and the shelf waters display complex thermal characteristics with distinct temperature gradients separating these three water masses. This type of information can be very useful for increasing our understanding of many physical phenomena that occur over Earth's oceans.     

Amygdalar and hippocampal theta rhythm synchronization during fear memory retrieval

The amygdalohippocampal circuit plays a pivotal role in Pavlovian fear memory. We simultaneously recorded electrical activity in the lateral amygdala (LA) and the CA1 area of the hippocampus in freely behaving fear-conditioned mice. Patterns of activity were related to fear behavior evoked by conditioned and indifferent sensory stimuli and contexts. Rhythmically synchronized activity at theta frequencies increased between the LA and the CA1 after fear conditioning and became significant during confrontation with conditioned fear stimuli and expression of freezing behavior. Synchronization of theta activities in the amygdalohippocampal network represents a neuronal correlate of conditioned fear, apt to improve neuronal communication during memory retrieval.     

Frequency of Mutations Induced by Radiations in Hexaploid Species of Triticum

The frequency of visible mutations induced by x-rays, phosphorus-32, and sulfur-35 was calculated in six hexaploid Triticum species. The species with spelted ears and winter habit showed a much lower mutation rate than the freethreshing, spring wheats.     

湖南省水稻害虫天敌昆虫名录（一）

对湖南省水稻害虫天敌昆虫种类进行了调查，已查明天敌昆虫有３３１种，分属９目６５科２２１属．本文报道了其中的１４９种，分别记述了它们的寄主（猎物）和分布，并对少数优势种天敌的生物学特性作了记述．     

赤霉素(GA3)对武汉市露地梅花部分品种花期的影响

1998—2001年，研究了不同时间、不同浓度的赤霉素处理对露地梅花的始花期、盛花期、末花期及观赏期的影响，同时考察了梅花观赏质量(花径、展叶期、落蕾率)的变化，结果表明：2000mg／L的赤霉素处理对梅花花期具有调节作用，作用的方向与处理时间密切相关：10月底至11月处理提前；而1月处理又使始花期、末花期均延迟。赤霉素促使梅花花期提前的同时通常伴随开花量的下降；而在推迟梅花花期的同时开花量增加、且观赏期延长。赤霉素处理极显著地使‘江南朱砂’的花径缩短1．2—5．4mm；‘粉红朱砂’的展叶期提前3—4个月；‘粉红朱砂’出现明显的落蕾效应。研究还探讨了温度作为梅花开花的主导因子对试验研究的影响。