Carbon monoxide measurements in the troposphere

During the second flight of the space shuttle, the measurement of air pollution from satellites (MAPS) experiment in the OSTA-1 payload acquired approximately 35 hours of radiometric measurements of the carbon monoxide mixing ratio in the middle troposphere, upper troposphere, and lower stratosphere. A gas filter radiometer operating in the 4.67-micrometer band was used to acquire the data over the region from 38 degrees N to 38 degrees S during both daytime and nighttime. The performance of the measurement system was excellent. The data reduced to date indicate the presence of significant gradients in the middle tropospheric carbon monoxide mixing ratio with both latitude and longitude over the North Atlantic, the Mediterranean Sea, and the Middle East. On the basis of comparisons with directly measured values, the accuracy of the measurements is approximately 15 percent. Comparisons of data taken on successive orbits over the same geographic region indicate that the repeatability of the measurements is approximately 5 percent.     

Spray aiming in bombardier beetles: jet deflection by the coanda effect

Bombardier beetles of the carabid subfamily Paussinae have a pair of flanges, diagnostic for the group, that project outward from the sides of the body. Behind each flange is a gland opening, from which the beetles discharge a hot, quinone-containing secretion when disturbed. The flanges are curved and grooved and serve as launching guides for anteriorly aimed ejections of secretion. Jets of fluid, on emergence from the gland openings, follow the curvature of the flanges and are thereby bent sharply in their trajectory and directed forward. The phenomenon is illustrative of the Coanda effect, widely applicable in engineering and responsible for the familiar tendency of liquids to curve around spouts and down the front of containers when being poured.     

Advances in process control

Advances in electronics and computers have enabled industries to attain better control of their processes with resulting increases in quality, productivity, profitability, and compliance with government regulations. With a hierarchy of computers, distributed data acquisition, and information processing and control, it is possible to achieve overall optimum performance of a plant. While further advances in microprocessors and large-scale integration will be useful to the process engineer, major improvements in process control await advances in sensor technology and software.     

土壤保持耕作——全球农业可持续发展优先领域

 从农业活动对全球变化以及对农业可持续发展的影响进而导致全球性土壤保持需求的迫切性增加出发，追踪了国外土壤保持耕作领域的研究和发展动态；对中国该领域研究发展现状和研究水平，从时间、深度、方法、生产应用等方面与国外进行了比较分析。中国是一个水土流失和耕地退化严重的农业大国，而从全球统计数字来看，中国土壤保持耕作面积目前仅占全球保持耕作面积的0.2%，仅占全国耕地面积的0.1%， 其现状与中国耕地资源和环境的继续退化以及对土壤保持耕作需求的增加极不相符。加强中国土壤保持耕作系统研究和土壤保持耕作"节能固碳"长期建设不仅对中国而且对全球变化及农业可持续发展具有重大意义。鉴于中国土壤保持耕作领域研究和发展所存在的不足和所面临的更大挑战，以及该领域研究涉及到复杂的农业系统"耕作管理-生物过程-环境变化"相互作用及其系统能流-碳流循环过程，尤其农业生态系统碳汇/源估量尚存在诸多不确定性因素等科学问题，有必要运用综合的系统性研究分析方法，借助国外长期试验和理论研究经验，以及系统模型模拟研究手段等多学科和交叉学科知识，加速提升中国土壤保持耕作领域的科研实力和水平，为实现碳汇/源科学调控管理、减缓农业对温室效应贡献、促进农业可持续发展提供科学依据。     

Development of mulberry varieties for sustainable growth and leaf yield in temperate and subtropical regions of India

Sericulture is an agro-based industry, which heavily depends on mulberry (Morus spp.) for its sustainability, as mulberry leaf is the only available feed for the silkworm Bombyx mori L. Sericulture, in West Bengal and other subtropical regions in India, suffers from lack of adequate quantity of quality mulberry leaf during the colder months, the best season for rearing the high yielding bivoltine silkworm hybrids. In order to develop mulberry varieties, which can sustain normal growth during these colder months to yield better, efforts have been made in different research institutes in India. The present report is part of such an effort in which accessions in germplasm bank were screened for better growth, leaf retention and leaf yield contributing associated traits. Twenty three selected parents were crossed, 3,500 seeds were sown, 2,700 seedlings were transplanted to progeny row trail, selected 210 hybrids were evaluated under primary yield trial and finally nine hybrids along with a control variety were studied in detail for all leaf yield contributing traits under final yield trial. Stability analysis was adopted to identify hybrids, which can yield stably across seasons. The hybrids CT-44 and CT-11 out yielding the control by 17.17 and 7.11% were selected as these hybrids yield 7.93 and 8.15 mt/ha leaf respectively during the colder months (February) for their direct use as cultivars in West Bengal and other subtropical areas of India to sustain bivoltine sericulture to produce quality and gradable silk fibers.     

Assessment of the uniformity and stability of grapevine cultivars using a set of microsatellite markers

Solidity of microsatellite markers is a key issue for varietal identification, especially when they are used for legal purposes, what includes their probable future use in the distinctness, uniformity and stability testing of new varieties needed for the granting of Plant Breeders’ Rights. Nine grapevine microsatellites (VVS2, VVMD5, VVMD27, VVMD28, ssrVrZAG29, ssrVrZAG62, ssrVrZAG67, ssrVrZAG83 and ssrVrZAG112), which had previously demonstrated its capacity to discriminate any grapevine variety, have been assessed to evaluate its uniformity and stability. 19 varieties were selected, representative of a high diversity for morphological, agronomical, cultural and historical aspects, as well as for microsatellite allele variability. Then, for each variety, uniformity and stability were evaluated through the analysis of 50 plants from each of three different plots, and five plants from each of seven additional plots. Material from 4,137 plants of 229 plots of the 19 varieties was sampled in seven countries. Of 3,654 plants analyzed with the set of nine microsatellites, 3,299 were of the right variety and used for the survey. An average of 172 individual values was studied for each allele of each microsatellite of each variety, and none differences were detected that could not be explained as technical variations, with the exception of several putative chimeras in two varieties. Of the total of 171 variety x microsatellite combinations, only in one combination (‘Merlot’ x VVMD27) the number of off-types exceeded the threshold allowed. The remaining 170 combinations have been found uniform and stable according to internationally accepted rules.     

Analysis of rice blast resistance gene <Emphasis Type="Italic">Pi</Emphasis>-<Emphasis Type="Italic">z</Emphasis> in rice germplasm using pathogenicity assays and DNA markers

The Pi-z gene in rice confers resistance to a wide range of races of the rice blast fungus, Magnaporthe oryzae. The objective of this study was to characterize Pi-z in 111 rice germplasm accessions using DNA markers and pathogenicity assays. The existence of Pi-z in rice germplasm was detected by using four simple sequence repeat (SSR) markers (RM527, AP4791, AP5659-1, AP5659-5) closely linked to Pi-z, and was verified using pathogenicity assays with an avirulent strain (IE1k) and two virulent races (IB33 and IB49). Among 111 germplasm accessions evaluated, 73 were found to contain the Pi-z gene using both SSR markers and pathogenicity assays. The remaining 38 germplasm accessions were found to be inconsistent in their responses to the blast races IB33, IEIk and IB49 with expected SSR marker alleles, suggesting the presence of unexpected SSR alleles and additional R gene(s). These characterized germplasm can be used for genetic studies and marker-assisted breeding for improving blast resistance in rice.     

Combining ability of low phytic acid (<Emphasis Type="Italic">lpa1</Emphasis>-<Emphasis Type="Italic">1</Emphasis>) and quality protein maize (QPM) lines for seed germination and vigour under stress and non-stress conditions

Grain yield is more likely to be compromised by poor seed germination and vigour in low phytic acid (LPA) and quality protein maize (QPM) than normal maize (Nm), especially when grown under stressful tropical environmental conditions. The objectives of this study were to determine the effect of stress conditions on seed germination and vigour traits (percentage germination, seedling dry weight, average root and shoot length and vigour index) and to determine the GCA effects of the parental lines and SCA effects of the crosses. A ten parent half diallel (LPA, Nm, QPM lines) was subjected to the standard germination (non-stress) and accelerated aging (AA) (stress) tests. All seed lots were at the same physiological age and produced under the same season and conditions. Genotypic and group differences were investigated. General combining ability (GCA) and specific combining ability (SCA) effects were significant (P ≤ 0.001) for all traits under both stress and non-stress conditions indicating that both additive and non-additive gene effects were significant. Generally SCA effects were superior for all traits. The LPA lines displayed 61 % reduction in germination and 23–52 % reduction in vigour under stress conditions thereby underscoring challenges that are expected in deploying LPA maize in stress conditions. However, LPA line CM 31 exhibited large positive and mostly significant GCA effects, while two LPA × LPA crosses showed significant positive SCA effects. Results indicate breeding is required to improve both germination and vigour of the LPA lines to adapt them to tropical conditions that are generally stress-prone.     

Characterisation of resistance to crenate broomrape (<Emphasis Type="Italic">Orobanche crenata</Emphasis> Forsk.) in <Emphasis Type="Italic">Lathyrus cicera</Emphasis> L.

Field, pots and mini-rhizotrons experiments revealed the existence of useful levels of avoidance and resistance to Orobanche crenata Forsk. within Lathyrus cicera L. accessions, in addition to escape due to precocity or to reduced root biomass. This resistance was characterized by several phenotypic mechanisms of defence which acted alone or in combination, including low stimulation of parasitic seed germination, prevention of the radicle penetration inside the root and prevention of a correct connection by the parasite with the host vascular tissue being visible by reduced development of established parasitic tubercles or abortion of the parasitic tubercles formed.