谷子生育过程中同工酶的变化

以１２个谷子品种为材料，分析了谷生育期的酯酶同工酶和过物酶同工酶的变化，结果表明，两种同工酶因生育期不同而呈规律的变化，芽期是两种同工酶酶谱最稳定最丰富的时期，苗期是两种同工酶表现的最低水平时期。随植株的生长发育，酯酶同工酶的酶带逐渐增加，酶活性不断增强，随植株的生长发育，过氧化物酶同工酶ＰＸ２区的酶活量不断增加，而ＰＸ３区则相反，随植株的生长发育，酶活量有规律地减弱。     

谷子品种资源及其近缘种酯酶同工酶的研究

本文收集国内不同地区的谷子品种120个,以及狗尾草、谷莠子和御谷等材料,采用聚丙烯酰胺凝胶电泳法进行了酯酶同工酶分析.谷子芽期的酯酶同工酶酶带共出现19条,所得酶谱分成31个类型.从地理分布来分析,黄土高原区和内蒙古高原区品种酯酶同工酶类型丰富.从谷子品种的起源和演变来分析,谷子和普通狗尾草的酶谱大致相同.研究表明,酯酶同工酶重复性好,比较稳定,可以做为谷子分类学和研究谷子进化关系的一个生化指标.     

Evaluation of the Forage Potentials of Pearl Millet in a Semi-arid Tropical Environment

The pastures and rangelands of the semi-arid region of Nigeria wherein is the bulk of the livestock in the country, provide sufficient nutrients for livestock for no more than three to five months of the year. There is therefore need to have high yielding and good quality forages to ensure adequate all-year-round forage supply for the livestock. The objective of this study was to evaluate the forage potentials of pearl millet ( Pennistetum americanum [L.] K. Schum.) which is well adapted to the region. Twenty cultivars were evaluated for their growth, forage yield and mineral content potentials.
The cultivars were significantly different in the number of leaves per plant, plant height, dry matter yield and potassium content in each cutting. Differences in crude protein and crude fibre contents were significant only between cuttings. Variations in crude protein and crude fibre contents ranged from 14.1 to 20.3 % and from 28 to 30.8 %, respectively. Cultivars had a progressive dimunition in growth, yield and mineral content potentials after the first or second cutting. Pearl millet therefore seems less suited to forage production in the semi-arid region of Nigeria since no cultivar showed the potentials for adequate supply of all-year-round forage.     

不同类型大豆酯酶同工酶研究

１９９１年对１５２份栽培大豆、１２份野生大豆、１２份半野生大豆进行了胚芽期酯酶同工酶分析。研究表明：不同类型大豆酶谱类型丰富，１７６份品种表现为１７个类型。按其迁移率可分为Ｅ１－Ｅ８８个大区。Ｅ４、Ｅ６和Ｅ７区酶带条数稳定，酶带着色深，构成了大豆胚芽期酯酶同工酶的特片性酶带。按照地理分布，黄河流域的大豆类型酶谱最为丰富，共１５种类型，其中山西、河南大豆表现较特殊类型。东北三省的酶谱类型们居第二，为     

中国高粱芽期酯酶同工酶研究报告

1981-1984年间进行了以中国高粱为主的幼芽期酯酶同工酶研究。供试材料包括中国高粱品种928份,另有一些国外和野生高粱材料,共计949份样品。电泳分析结果表明:高粱幼芽期酯酶同工酶是遗传稳定的特性。中国高粱的酶谱带一般为9-14条,最多19条,最少4条。可划为 E_1至 E_9九个谱带区,其中 E_4是主酶带区,E_6、E_7是次主酶带区。这些酶谱带可分为七大类、17个类型,其中以Ⅱ-2、Ⅱ-3、Ⅱ-4三个类型最为普遍,占928份中的81.9%,是中国高粱的主体类型。但品种间的谱带变异也很丰富,非洲、印度高粱所表现的谱带类型,中国高粱基本上都有。与供试的野生高粱相比,二者之间相似处多于不同处,特别是与帚枝高粱更为接近。看来 E_4区是蜀黍属共同的主酶带区。至于中国高粱与外国高粱以及野生高粱的亲缘关系,尚需做进一步深入研究。     

Drought Tolerance Aspects in Pearl Millet

Different indices for selection of lines grown under low and high water levels were examined from both theoretical and practical standpoints. Pearl millet ( Pennisetum americanum (L.) K. Schum) was planted under a sprinkler irrigation gradient in 1983 and 1984. Equations were developed for drought tolerance for both yield and forage production. Correlation coefficients were developed for yield and yield components.
The equations showed that drought will generally result in decreased productivity of both grain and forage. Grain yield was found to be positively correlated with seed weight and with the number of seeds in the main head, and negatively correlated with plant height under low water level. Dry matter was positively correlated with tiller number.     

Chlorophyll Content, Hill Reaction and PEPcase Activity in Relation to Hybrid Vigour in Pearl Millet during Early Seedling Growth

Three hybrids of Pennisetum americanum L. Leeke were analyzed for growth and photosynthetic components during early growth and compared with their respective parents. Growth in terms of shoot length, fresh weight and dry weight along with the chlorophylls, and Hill activity revealed better parental and/or mid parental heterosis in all the hybrids over their respective parents. However, PEPcase activity displayed heterosis only in BJ-104. In other two hybrids no heterosis over the parents could be observed indicating thereby that the activity of this enzyme may not be rate limiting in parental lines.
Nevertheless, it appears that in pearl millet hybrids improved photosynthetic apparatus as observed in chlorophyll contents and Hill reaction may be one of the early expressions of hybrid vigour.     

不同育种年代玉米自交系和杂交种的过氧化物酶和酯酶同工酶的研究

对不同育种年代的１１个玉米自交系和８个杂交种进行了过氧化物酶和酯酶的同工酶研究。结果表明，用过氧化物酶同工酶区分不同材料的灵敏性高于酯酶同工酶。尽管不同育种年代玉米自交系和杂交种在同工酶谱带上差异明显，但未表现出随育种年代变化的趋势。根据过氧化物酶同工酶或酯酶同工酶谱带的变化很难预测玉米杂种优势的表现。     

Trait Associations in Introgressed Populations of Pearl Millet

Principal component analysis has been used in this study to describe the associations among 17 traits measured on progenies developed from matings of two adapted pearl millet inbreds with three exotic pearl millets. The exotic parents were a primitive I and race, a weedy relative, and a wild relative. The first three components were calculated for these matings and the associations defined. Correlations between these components and grain yield and growth rate were also determined. The first principal component described a hybrid index in five of the six matings, and a number of other complexes of traits were determined by this component or the other two. Some were common to several matings. The first three components accounted for only 50–60% of the total variability; thus no strong association of trans was found that would hinder recombination of parental types to select agronomically desirable segregates with high grain yield or growth rate.     

Effect of Drought and Nitrogen Availability on Osmotic Adjustment of Five Pearl Millet Cultivars in the Vegetative Growth Stage

Growth of pearl millet (Pennisetum glaucum (L.) R. Br.) is affected in areas with limited and erratic rainfall, often combined with nitrogen deficiency. Therefore, effects of severe drought and nitrogen availability on mechanisms of dehydration avoidance were investigated. Five pearl millet genotypes were cultivated in soil differing in nitrogen availability, low (N1), medium (N2) or high (N3) in a climate chamber. Thirty‐five days after sowing, the plants were exposed to drought for 12 days. Drought decreased leaf area and stomatal conductance strongly and caused leaf rolling. In the youngest fully expanded leaves, drought led to an osmotic adjustment from around ?0.5 to ?0.9 MPa, in N1 and N2 substantially achieved by potassium accumulation. Nitrate contributed to the osmotic adjustment in N2 and N3, proline only slightly, increasingly from N1 to N2, whereas the sum of glucose, fructose and sucrose did not play a role. The dehydration independent osmotic force for water uptake (osmotic potential at full turgor) was under drought strongest at N2 and in the landrace Dembi Yellow stronger than in the cultivars Ashana and Ugandi. This contributed to the higher relative water content (RWC) of ‘Dembi Yellow’, whereas due to other factors nitrogen had no effect on the RWC.     

Genetic Analysis of Isozyme Loci in Chives (Allium schoenoprasum L.)

The inheritance ot nine isozyme systems in selfed progenies of chives was studied elcctrophoretically. The isozyme systems studied were malate-dehydrogenase (MDH), phosphoglucoisomerase (PGI), triosephosphate-isomerase (TP1), diaphorase (D1A), menadione-reductase (MDR), esterase (EST), glutamate-oxalacetate-transaminase (GOT), hexokinase (HK) and superoxide-dismutase (SOD). Segregation results of Goodness-of-Fit tests against the expected 1:2:1 and 3 : 1 ratios for codominant and dominant inheritance, respectively, led to the identification of 16 isozyme loci whose banding patterns are given in this paper. The first results on linkage relationships between isozyme loci and between the Mdr-3-locus and a male sterility gene are given. These results and further studies will be used to mark important characters in chives.     

普通小麦T型和K型胞质雄性不育系败育过程细胞学观察和同工酶检测

利用细胞学观察和同工酶电泳测试，分析了普通小麦Ｔ型和Ｋ型胞质雄性不育系、保持系和恢复系花药的发育过程，结果表明：（１）用同工酶电泳检测小麦Ｔ型和Ｋ型雄性不育胞质效应的区别有效。（２）酯酶酶谱较过氧化物酶酶谱更能清楚地检测两类不同胞质不育系败育发生的时期和程度。（３）细胞学观察表明，Ｔ型不育系小孢子在双核期其细胞核绝大部分不存在，成为空壳，败育较早，较迅速，这可能是其恢复源较狭窄的原因之一；而Ｋ型不     

The Potential for Exploiting Variation in Salinity Tolerance in Pearl Millet (Pennisetum americanum (L.) Leeke)

Shoot and root growth and plant dry weight were determined for twenty four accessions of pearl millet, Pennisetum americanum (L.) Leeke, after two weeks growth in saline solution culture at EC 20 dS m^-1. The EC was achieved using NaCl + CaCl₂ 1:1 by weight in solution culture. Although salinity markedly inhibited growth of all accessions, three, 93613, KAT/PM-2 Kitui, and Kitui local produced significantly greater dry matter, and they and 93612 had longer shoots than the other accessions. Accessions WCA 78 and Bulk 7704 were highly sensitive to salinity in all 3 characters measured. There was considerable variation between the 24 accessions, suggesting that selection for increased tolerance to salinity in pearl millet should be possible. This was examined using normal seed of the cultivar Al/3. A first cycle of selection screened 16,000 seeds after 15 days growth in nutrient solution at EC 26 dS m^-1. 106 individuals were selected to form the S₁ selection line. Selected seedlings were grown to maturity and polycrossed. In a second cycle of selection, 30,000 S₁ polycross progeny were screened as previously, but at EC 30 dS m^-1. A selection intensity of 0.08% was achieved. The selected plants were again grown to maturity and again polycrossed. Efficiency of the selection procedure was assessed from comparison in sand culture of the performance of the selected line with the unselected Al/3 line and Kitui local which from the previous assessment of the 24 accessions was rated as relatively salinity tolerant. The selection line was superior to the other two lines at four salinity levels. The results of this study suggest that further improvement in salinity tolerance in pearl millet may be expected from further selection and breeding, using the methods described here.     

Effectiveness of Ethrel as a Male Gametocide in Pearl Millet and its Influence on Ergot

In field and greenhouse experiments Ethrel (2-chloroethyl phosphonic acid) was tested for its male garnetocidal effects on pearl millet (Pennisetum americanum) and its subsequent effects on ergot development. Application of Ethrel at 2000 ppm at late boot or early protogyny was the most effective for inducing male sterility in the hybrid, EJ 104. Female fertility in a male sterile line, however, was not affected by Ethrel treatment. Ethrel at 2030 ppm applied at ihe late boot stage resulted1 in partial paniele exsertion, and reduced plant height anc. panide length. In vitro Ethrel (2000 ppm) completely inhibned pollen germination but did not affect germination of conidia of Claviceps fusiformis, the causal agent of ergot of pearl millet. Ergot resistance or susceptibility in pearl millet lines was not affected., probably because Ethrel could not induce complete male sterility.     

Peroxidase Isozyme Pattern in Pearl Millet Lines Resistant and Susceptible to Downy Mildew

Peroxidase isozyme patterns of five downy mildew (DM) resistant inbred lines (PIB-57-1, PIB-1248, PIB-1356, PIB-1364 and PIB-1440), five susceptible lines (PIB-1335-1-1, PIB-1314-2-2, PIB-2231-1, 7042 and PIB-1530-1-1) and DM free plants from the susceptible lines of pearl millet were studied. The results suggested a possible involvement of an isoperoxidase (C9) in imparting the resistance. The involvement of two other isozymes (C5 and C6) was also indicated in the1 resistance mechanism. The specific differentiation m particular isozyme pattern can be a useful criterion for characterization of resistance to downy mildew.     

不同基因型谷子的RAPD分析

利用随机多态性DNA (RAPD)分子标记技术分析了9种不同基因型谷子的遗传差异.采用20个随机引物对谷子基因组DNA进行RAPD-PCR扩增,共得到616条带,其中多态性条带有389条,多态性比例达到了63.2％.聚类分析表明,以遗传相似系数为0.68处可将9个谷子品种划分为3类.     

Observed and Predicted Genetic Gains from Single and Multi-Trait Selections Using Three Mating Designs in Pearl Millet*

The objectives of the study were to estimate the genetic components of variance, predict the response to selection and to evaluate observed response to selection using two populations namely, PSB 7 and PSB 3, of pearl millet (Pennisetum americanum [L.] Leeks). The observed response was studied using four methods of selection based on single and multitrait criteria in three types of families, namely S1, half-sib (HS) and full-sib (FS) families. One hundred SI, HS and FS families each were developed in PSB 7 and PSB 3. Plants within a population were pollinated with bulk pollen of other population to develop HS families. Crosses were made between a pair of plants using one plant from each of the two populations to develop PS families. Data were recorded on days to flower, plant height, tiller number, spike length, spike girth, seed yield per plant and spike weight. Additive genetic variance estimates were significant for all traits. The estimates of dominance and additive × location and dominance × location interaction components were not significant, except additive × location component in PSB 7 for seed yield and spike weight. The genotypic component of variance among S1 families and S1 × location interactions were significant except S1 × location interactions in PSB 7 for days to flower, spike length and spike girth. Twenty-four strains were developed by intermating superior families identified on the basis of four selection methods in each of the six types of families. The selection methods were high seed yield (YS) per se; index selection (IS) for high tiller number and long and thick spike; truncation selection (TS) for high yield among the families having days to flower and plant height lower than the population mean: and visual selection (VS) after completion of flowering for good vigour, uniformity in plant height and good inflorescence attributes. YS and IS were found to be superior to TS and VS with respect to observed genetic gains for seed yield. That advance was higher in selection among SI families as compared with FS and HS families. In general, a good agreement was noted between observed and expected responses. Expected genetic gain from FS reciprocal (R) recurrent selection was higher than the average gain from HS-R selection.     

光照条件及无机营养对谷子结实的影响

光照条件及无机营养是影响谷子(粟)结实的重要生态因子.从抽穗到抽穗后20天遮光处理对谷子结实有严重影响.用1层、2层和3层纱布遮光,秕谷率分别增高6.18%、25.67%和37.56%,成粒数分别减少33.44%、43.56%和63.08%.遮光程度和秕谷率、成粒数的相关系数分别为0.98和-0.98.氮素营养水平与颖花数、秕谷率的相关系数分别为0.9699和-0.9798.氮素营养在谷子抽穗前18天和抽穗后20天对结实影响最大,此时提高氮素营养水平,秕谷率比对照降低7.22%和9.87%.氮素营养对结实的影响同时也受降水的制约.磷、钾、硼等元素对谷子结实也有明显的影响.本文从生理上分析了光照条件和无机营养对谷子结实的影响.     

刺五加种子休眠解除过程中过氧化物酶和酯酶同工酶的变化

剌五加种子用100 mg/L赤霉素(gibberellin,GA)浸泡后进行变温层积(15～18℃14周,2～6℃14周)处理。层积16周后,种子开始萌发,GA处理种子的萌发率明显高于对照,在28周时,GA处理的萌发率达到69.33%,而对照只有50%。在实验期间,聚丙烯凝胶电泳始终能够检测到1条过氧化物酶(peroxidase,POD)和1条酯酶(esterase,EST)同工酶带,GA处理促进这两条同工酶带的表达。与对照相比,GA处理使层积16周出现的POD新条带更强,使EST新条带提前(第12周)出现(对照在第16周)。结果表明,外源GA处理促进层积打破刺五加种子休眠的效应,GA的这种效应与促进POD和EST同工酶的基因表达有关。