水分缺乏始期对玉米产量组成的影响

已报道过玉米籽粒产量对从大约吐丝开始直到灌浆这一期间内的缺水特別敏感。然而,胁迫始期对玉米产量及产量组成的影响尚不清楚。Robins等(1953)和Denmead(1960)等均报道过,从抽雄到吐丝后一周发生胁迫会造     

适应300马力以下的机动渔船——YSF50—1型油水分离器

由江苏省专业生产的“YSF50—1型油水分离器”,经性能测试表明,符合我国船检局1987年《内河船舶防污染结构与设备规范》关于排放污水含油量小于15毫克/升的要求。我国沿海港口星罗棋布,群众渔业300马力以下的机帆渔船数量可观,每当渔船返航云集港湾,渔船机舱排放的废水污染水质,给当地居民生产、生活用水带来困难,为此,有关部门规定了船舶的排     

Air ion exposure system for plants

A system was developed for subjecting plants to elevated air ion levels. This system consisted of a rectangular Plexiglas chamber lined with a Faraday cage. Air ions were generated by corona discharge from frayed stainless steel fibers placed at one end of the chamber. This source was capable of producing varying levels of either positive or negative air ions. During plant exposures, environmental conditions were controlled by operating the unit in a growth chamber.     

Elimination of toxicity from polyurethane foam plugs used for plant culture

Polyurethane foam plugs commonly are used as collars or supports to grow plants in solution culture. Despite their utility, these foam plugs can be quite toxic to plants, particularly to small seedlings. We have observed tissue injury in tests using plugs to support lettuce, red beet, and potato plants in solution culture. Typically, the injury is initiated on the hypocotyl or stem tissue in direct contact with the foam, and appears within 30 hr as a brownish discoloration on the tissue surface. This discoloration can be followed by complete collapse of affected tissue and eventual death of the seedling. When injury does not progress beyond surface browning, the seedling survives but growth is slowed. In this paper, we report on different treatments that can be used to remove the toxicity of these plugs so they can be used in plant research.     

Growing plant in space

Space agencies in several countries are planning for the culture of plants in long duration space bases. The challenge of developing crop production procedures suitable for space projects will result in a new approach of problems we may meet today or in the near future in our common production systems. You may keep in mind subjects as: minimizing wastes or pollution problems, saving materials, introductions robotic helps. Discussion between scientists involved with food production for space programmes and protected horticultural cultivation may open new perspectives.