叶片是植物最主要的光合作用器官,是水稻的源器官。其生长、发育和衰老的分子机理的研究对水稻经济产量和生物产量具有重要的意义。2006年我单位在参加农业部实践8号卫星航天育种工程的空间辐射诱变籼稻（Oryza sativa L.indica）泸恢H103中得到一叶片早衰突变体。初步研究结果表明,该早衰叶突变体表现的特点是：抽穗期前心叶抽出时,先前抽出的倒4叶片就开始变黄衰老,抽穗初期时先前抽出的倒3叶表现衰老,抽穗后期先前抽出的倒2叶表现衰老,灌浆期剑叶表现衰老,完全成熟时剑叶完全衰老死亡。利用该突变体分别与其野生型泸恢H103、R527、R602杂交,获得F1及其衍生的F2群体,对早衰叶突变体进行遗传分析。遗传分析表明由一隐性核基因psl2控制。本研究为最终定位和克隆目标基因奠定了基础。[著者文摘] | Plant leaf is the most important organ for photosynthesis, and it is the source organs of rice. The research on growth, development and molecular mechanism of aging have great significance to the economic and biological yield of rice. We obtained senescence mutant from leaves of the rice Luhui-H103 （Oryza sativa L. indica） after space radiation mutagenesis in the 8th unit of satellite space breeding projects of the ministry of agriculture in 2006. The preliminary findings showed that the representative features of senescence leaves mutant were follow： the four leaves from root which were putting out previously began to turn yellow and aging when the centre leaf put out before heading stage; In the initial stage of heading, the three leaves from root were aging; The two leaves from root were aging at the later stage of heading; Flag leaf was senescent in pustulation period, and the flag leaves were senescent completely and dead when the spikes were full maturity. The mutants were crossed with their wild-type Luhui-H103, R527 and R602, respectively, obtained the F1 and F2 groups, and using them for genetic analysis of premature aging leaf mutants. Genetic analysis showed that the mutant was controlled by a recessive nuclear gene psl2. This research laid the foundation for the final mapping and cloning of the target gene.[著者文摘]

[Objective] The aim was to study the sensitive response characteristics of the main agronomic traits of somaclonal and the variation of sensitive response of the lines of somaclonal to sowing date. [Method] The RITSD changing of agronomic traits was studied by using 24 rice somaclonal and its donor parent under two sowing dates. [Result] The average values of R ITSD were higher (over one) for the traits of pant height (PH), density of spikelets (DS), filled spikelets per panicle (FSP), spikelets per panicle (SP) and grain weight per plant (GWP), but lower for days of sowing to heading (DSH), effective panicles (EP), panicle length (PL), seed setting rate (SS) and 1000-grain weight (1 000-GW). These showed that PH, DS, FSP, SP and GWP were easily affected by sowing date and tended to higher with the later sowing; the RITSD of somaclonal changed with the agronomic traits. The frequency of RITSD’ variation of DSH and PH was higher than that of PL. The RITSD’ value of EP, PL, DS, FSP, SP and SS became higher, and higher or lower for DSH and GWP in different somaclonal; compared with the donor, 20 of 24 was significantly different, and the frequency of RITSD variation was over 83. 3%, however, RITSD of the most lines (75 %) changed only for 1 - 2 characters; cluster analysis showed that the RITSD of agronomic traits belonged to different combinations of somaclonal in rice. [Conclusion] the study had provided a theoretical basis for the screening and using of the somaclonal.

Eighteen accessions of Sorghum bicolor used for the present study consisted of 4 genotypes of forage sorghum i.e. UPFS-34, Pant Chari 4, UP Chari 2 and UP Chari 3 and 14 genotypes of grain sorghum. The seed of most of the genotypes of forage sorghum was reddish brown but the colour of the seed of grain sorghum was grayish. However, genetic variation at DNA level among 18 accessions of sorghum revealed that 3 forage sorghum out of 4 may have diverged long time back in evolution but one of these i.e. UP Chari 2 may have evolved as a forage variety much later. The results suggest that forage sorghum might have evolved by gene arrangement of grain sorghum. In UP Chari and Swathi most of the genotypic characters are the same but there might be changes in gene patterns responsible for forage characters. However, three forage sorghums which got diversified indicate that most of the genotypes of forage sorghum were distantly related to grain sorghum.

Dissertation (MScAgric)--University of Pretoria, 2011. | Marama bean (Tylosema esculentum (Burch) A. Schreib) is an underutilised, drought- tolerant legume native to the semi-arid areas of Botswana, Namibia and South Africa. The edible seeds of marama beans are good sources of protein and fat, and its flours can potentially enhance the nutritional quality of sorghum porridge, a staple in many African countries. Sorghum has a low protein content and is deficient in lysine. Compositing sorghum with lysine-rich marama flour when preparing porridges would address this problem. Utilisation of marama flour in composite porridge depends on sensory acceptance. In this study nutritional and sensory quality of marama-sorghum composite flours and porridges are investigated. Full fat and defatted flours from unheated and dry heated (150 °C /20 min) marama beans were composited with condensed tannin-free sorghum meal (30:70). Marama flours, sorghum meal, marama-sorghum composite flours and porridges were analysed for proximate composition, amino acid composition, energy value, fatty acid composition, total phenolic content and antioxidant activity. Porridges (10% solids) were subjected to descriptive sensory analysis, consumer acceptance test (n=52), texture analysis, pasting profiles and colour measurements. Sorghum porridge and porridge composite with full fat marama flour from heated beans were more acceptable than other composite porridges. Compositing sorghum meal with marama flour reduced the cooked sorghum aroma/flavour intensities prominent in sorghum porridge. Dry heating marama beans prior to milling resulted in a roasted nutty flavour in the final product. Porridges from heated marama beans were darker in colour than porridges from unheated beans. This could be attributed to flavour and colour development due to Maillard reaction during dry heating. Composite porridges from full fat marama flours were described as buttery/creamy. A bitter taste and aftertaste was perceived in porridges from defatted flours. Presence of fat seems to mask bitterness in porridges. Marama-sorghum composites and Tsabotlhe porridges were less viscous than sorghum porridge. This was confirmed by pasting profiles (low final viscosities) and texture analysis indicating reduced firmness. Starch contributes greatly to the textural properties of sorghum porridge. Marama flour has no starch. Compositing the flour with sorghum reduced starch levels in the composite porridges. This explains the reduction in viscosity and firmness of the porridges. Compositing sorghum meal with marama flours significantly increased protein and fat contents in flours and porridges. The fat content in marama-sorghum flours was in the range of 5.6 to 14.6%. Protein increase ranged from 61% to 96% in marama-sorghum composite porridges compared with sorghum porridge. There was 11-24% energy value increase in marama-sorghum composite porridges compared with sorghum porridge. Porridges composited with full fat flours contributed to higher energy values than those composited with defatted flours. This is because of fat energy contribution. Lysine content in marama flour was significantly higher than sorghum meal. Lysine content was 3 to 4 times higher in marama-sorghum porridges than in sorghum porridge. Unsaturated fatty acids were the most present in both marama-sorghum composite porridges and sorghum porridge. There was an increase in oleic acid as marama flour was composited with sorghum. Marama flours had higher levels of total phenolics than sorghum flour. Marama flour has high levels of tyrosine which could react with the Folin Ciocalteu reagent thus leading to an increase in measurable phenols. Marama flours from dry heated beans had higher total phenolic content and antioxidant activity than flours from unheated beans. Heating may have increased phenolic compound extractability due to release of bound phenolics. There was a positive correlation between the total phenolic content and antioxidant activity (r = 0.80, p < 0.05) in all samples. Findings from this study indicate that marama flour can potentially be used to improve the nutritional quality of sorghum porridges. Furthermore this study shows that use of full fat flour in marama-sorghum composite porridges give more acceptable sensory properties. | Food Science | unrestricted

The potential gene flow between a crop and its wild relatives is largely determined by the overlaps in their ecological and geographical distributions. Ecogeographical databases are therefore indispensable tools for the sustainable management of genetic resources. In order to expand our knowledge of Sorghum bicolor distribution in Kenya, we conducted in situ collections of wild, weedy and cultivated sorghum. Qualitative and quantitative morphological traits were measured for each sampled wild sorghum plant. Farmers’ knowledge relating to the management of sorghum varieties and autecology of wild sorghum was also obtained. Cluster analysis supports the existence of several wild sorghum morphotypes that might correspond to at least three of the five ecotypes recognized in Africa. Intermediate forms between wild and cultivated sorghum belonging to the S. bicolor ssp. drummondii are frequently found in predominantly sorghum growing areas. Crop-wild gene flow in sorghum is likely to occur in many agroecosystems of Kenya.

The potential gene flow between a crop and its wild relatives is largely determined by the overlaps in their ecological and geographical distributions. Ecogeographical databases are therefore indispensable tools for the sustainable management of genetic resources. In order to expand our knowledge of Sorghum bicolor distribution in Kenya, we conducted in situ collections of wild, weedy and cultivated sorghum. Qualitative and quantitative morphological traits were measured for each sampled wild sorghum plant. Farmers? knowledge relating to the management of sorghum varieties and autecology of wild sorghum was also obtained. Cluster analysis supports the existence of several wild sorghum morphotypes that might correspond to at least three of the five ecotypes recognized in Africa. Intermediate forms between wild and cultivated sorghum belonging to the S. bicolor ssp. drummondii are frequently found in predominantly sorghum growing areas. Crop-wild gene flow in sorghum is likely to occur in many agroecosystems of Kenya.

The potential gene flow between a crop and its wild relatives is largely determined by the overlaps in their ecological and geographical distributions. Ecogeographical databases are therefore indispensable tools for the sustainable management of genetic resources. In order to expand our knowledge of Sorghum bicolor distribution in Kenya, we conducted in situ collections of wild, weedy and cultivated sorghum. Qualitative and quantitative morphological traits were measured for each sampled wild sorghum plant. Farmers' knowledge relating to the management of sorghum varieties and autecology of wild sorghum was also obtained. Cluster analysis supports the existence of several wild sorghum morphotypes that might correspond to at least three of the five ecotypes recognized in Africa. Intermediate forms between wild and cultivated sorghum belonging to the S. bicolor ssp. drummondii are frequently found in predominantly sorghum growing areas. Crop-wild gene flow in sorghum is likely to occur in many agroecosystems of Kenya.

Until now, The experiment about the forage crop have been almost not conducted on the reclaimed land. Therefore, this experiment was carried out in order to know productivity of summer forage crop using slurry composting-biofilteration (SCB) liquid fertilizer on reclaimed land of Hwaong and Sukmoon in korea from 2008 to 2009. The forage crops used in this experiment were corn and sorghum × sorghum hybrid which are used as summer forage crops in South Korea. The experiment was treated with chemical fertilizer (CF), swine slurry (SS) and SCB liquid fertilizer. Dry matter (DM) yield of corn was higher than those of sorghum × sorghum hybrid in both reclaimed lands but the effect of SCB liquid fertilizer was not appeared. The neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents of corn were lower than those of sorghum × sorghum hybrid. The crude protein (CP) content and in vitro dry matter digestibility (IVDMD) of corn were higher than those of sorghum × sorghum hybrid. In generally feed values of corn were higher than those of sorghum × sorghum hybrid. The results of this study showed that summer forage crop cultivation using uses SCB liquid fertilizer on reclaimed land are possible.