Microsatellite Marker Based Assessment of Genetic Diversity among Cultivars, Landraces and Wild Relatives in Rice

India being the primary center of origin for rice had a very large treasure of local land races, most of which are out of cultivation today. The exact genetic potential and their differences from commercial varieties and the magnitude of heterogeneity still present in them are not well catalogued. Hence the need to characterize the available land races has become imminent in the modem day concept of crop improvement （Rezai and Frey, 1990）. The present study addresses the utility of SSR markers in divulging the genetic relationships at molecular level among the major component factions office gennplasm viz., local cultivars, land races and wild species collected from a wide range of agro-geographical regions of Indian subcontinent.     

Genetic Diversity of Peanut Core Collection from US Using Simple Sequence Repeats

Groundnut is a member of genus Arachis and the crop is divided into two subspecies and six botanical varieties based on morphological characteristics （Krapovickas and Gregory, 1994）. The International Crops Research Institute for the Semi-Arid Tropics （ICRISAT） holds more than 14 000 groundnut accessions from which a core collection of 1 704 have been developed （Upadhyaya et al., 2003）. Holdbrook et al. （1993） developed a groundnut core collection of 831 accessions from a total of 7 432 US groundnut accessions based on morphological characteristics. The large number and variability of accessions in GenBanks create problems in knowing which germplasm to select for breeding purpose. Only a few established cultivars and elite breeding lines have been utilised in breeding programmes. A core collection is a fraction of accessions from the entire collection which represent most of the available genetic diversity of the species. A core collection can extensively be evaluated and information derived from them can be applied to the whole collection. Identification of DNA markers associated with the botanical varieties of groundnut would be useful in genotyping, germplasm management and evolutionary studies.     

造型扦插之截干蓄枝式造型

截干蓄枝式造型的特点:因不纳弯,故枝条粗度可从1厘米至5厘米,最粗的可达10厘米以上。图1为2008年10月剪截的直径1厘米的对节白蜡,经生根粉药液处理后扦插于苗地培育,现洗去泥土裸根拍摄。     

辣椒新品种天椒14号的选育

天椒14号是以羊角椒自交系81为母本,以长羊角椒自交系145为父本配制而成的辣椒一代杂种。中早熟,株高97cm,开展度73cm,始花节位为第8~10节,果实羊角形,果长25.92cm,果肩宽3.17cm,果肉厚3.0mm,单果质量52.05g。青熟果深绿色,基部有褶皱,结果集中,连续结果能力强,辣味中等。田间对辣椒疫病、炭疽病和病毒病的抗性强于对照天椒4号。每667m~2产量4000kg以上,适宜甘肃及气候条件相似地区露地及保护地栽培。     

节能日光温室秋冬季双孢菇栽培技术

本文以蘑菇增温剂应用、肥料制作、追肥使用为主要内容，介绍了节能日光温室双孢菇秋冬季栽培管理技术，通过新技术的应用，去除了3～5次翻堆和后发酵，既节约生产成本，又减轻了劳动强度。通过应用维生素等进行补肥，提高了双孢菇产量。     

蔬菜经纪人赵永宽

江苏省东台市东台镇蟒河村村民种蔬菜开始于上世纪90年代前期，当时一家一户种植的蔬菜都是自己送市场，交通不便，路途又远，费工费力。遇到市场行情不好，只能眼睁睁地看着蔬菜烂在田里。菜农们为此很伤脑筋，这时赵永宽从外面打工回来，他在苏南打过工，见识广。脑子活，当起了蔬菜经纪人，他把村里一家一户种植的蔬菜收集起来，推向市场，取得了很好的经济效益。