Wiley
0011-183X
1435-0653
Cơ quản chủ quản: John Wiley & Sons Inc. , WILEY
Lĩnh vực:
Agronomy and Crop Science
Phân tích ảnh hưởng
Thông tin về tạp chí
Các bài báo tiêu biểu
Genotypic Responses in Sorghum to Drought Stress. III. Free Proline Accumulation and Drought Resistance<sup>1</sup> We explored a possible association between free proline amino acid accumulation in water‐stressed leaves and the drought resistance of various grain sorghum [Sorghum bicolor (L.) Moench] cultivars. Eight sorghum cultivars were grown in a growth chamber under a drying cycle (to a leaf water potential of −18 to −21 bars) and a subsequent recovery phase. Free proline, free ammonia, dark respiration rate, and recovery rating were recorded, as well as desiccation tolerance of each cultivar when grown in the field. Free proline accumulation was initiated in leaves of all cultivars as leaf water potential was reduced to −14 to −16 bars. Free ammonia concentration in leaves of all cultivars did not change appreciably during the drying cycle. Upon rewatering, free proline content was reduced and free ammonia concentration was increased, both rather abruptly. Cultivars difered significantly in maximum free proline accumulation and post‐stress free ammonia concentration, dark respiration rate, and recovery rating. Correlations indicated that desiccation tolerance was not related to any of the attributes measured, or even to recovery rating. Free proline accumulation during water stress was correlated significantly with post‐stress recovery rating, free ammonia concentration, and dark respiration rate. It is suggested that accumulated free proline in water‐stressed sorghum leaves is related to the ability of a cultivar to recover upon the relief of stress, possibly by way of proline's role as a source of respiratory energy in the recovering plant.
Tập 16 Số 3 - Trang 428-431 - 1976
Phosphorus and Potassium Fertilization Effects on Soybean Seed Quality and Composition ABSTRACT The effects of P and K fertilization on soybean [Glycine max (L.) Merr.] seed quality are unclear. Fertilization rates can have a positive effect on yield and composition in some growing locations and years but not in others. As the cost of soybean seed production increases, seed companies are interested in improving seed quality of soybeans possibly through increased soil fertilization. The objectives of this study were to determine the effect of different levels of P and K fertilization on soybean seed quality defined as seed viability, vigor, and seed composition. Seed samples were obtained from a long‐term P and K fertilization trial. Phosphorus and K treatments were 0, 28, or 56 kg P ha−1 yr−1 and 0, 66, or 132 kg K ha−1 yr−1 . Results indicated that excessive levels of P and K fertility decreased seed quality. Seed composition changed across sites and treatments, but changes were generally inconsistent. Total seed protein and oil were not significantly affected by P and K fertilization in most locations. However, linolenic acid concentrations increased with excessively high P and K fertilization while linoleic acid concentrations decreased only with P. These results indicate that excessively high levels of soil fertility may have negatively impacted seed quality.
Tập 53 Số 2 - Trang 602-610 - 2013
Inheritance of Resistance to Mexican Bean Weevil in Common Bean, Determined by Bioassay and Biochemical Tests Arcelin, a seed protein discovered in wild Phaseolus vulgaris L. accessions, gives high levels of resistance to the Mexican Bean Weevil [MBW; Zabrotes subfasciatus (Boheman)]. Five arcelin variants have been described. To better understand the genetic control of arcelin and MBW resistance, an inheritance study was conducted. Bioassay tests for insect response, and biochemical lasts to detect the presence‐absence of arcelin, were performed on the same individual seed. Accessions G12952 (arc‐4) and G02771 (arc‐5) had the highest level of resistance to MBW with no adults emerging from infested seed. Resistance was also found in G12882 (arc‐1) and G12866 (arc‐2), while G12922 (arc‐3) and the commercial cultivar, Pijao, were susceptible to the insect. The genetic study confirmed that all arcelin variants were inherited as a single dominant gene based on biochemical evaluations for presence‐absence of arcelin. Nevertheless, in bioassay tests with MBW, only crosses with arc‐1 and arc‐5 showed a single, completely dominant gene mode of inheritance, with the presence of arcelin being highly associated with resistance to the insect. For arc‐1 and arc‐5, biochemical tests can be reliably used to select for MBW resistance. For arc‐2, a combination of biochemical and bioassay tests is needed. As arc‐4 segregated few resistant individuals, and arc‐3 gave only intermediate to susceptible offspring, the use of these two arcelin variants is not recommended in a routine resistance breeding program. Electrophoretic patterns and bioassay tests of F1 and F2 generations showed that arc‐5 and arc‐1 variants are inherited as a single unit and are codominant.
Tập 33 Số 3 - Trang 589-594 - 1993
Nectar Production in Oilseeds: Food for Pollinators in an Agricultural Landscape Pollinating insects are in decline throughout the world, driven by a combination of factors including the loss of forage resources. The maize (Zea mays L.)– and soybean [Glycine max (L.) Merr.]–dominated agriculture of the Central and Midwestern United States produces a landscape relatively devoid of nectar and pollen resources. Introducing specialty oilseeds into current crop rotations could provide abundant floral resources for pollinating insects as well as a high‐value crop for growers. We investigated the nectar sugar resources and insect visitation throughout flower anthesis of nine specialty oilseed crops in west‐central Minnesota and eastern South Dakota during the 2013 and 2014 growing seasons. Total sugar produced over anthesis (TS) was highest for echium (Echium plantagineum L.) at 472 kg ha−1 . Canola (Brassica napus L.), crambe (Crambe abyssinica Hochst.), echium, borage (Borago officinalis L.), and cuphea (Cuphea viscosissima Jacq. × Cuphea lanceolata W. T. Aiton) produced enough sugar in one hectare to supply the annual sugar needs of a least one managed honey bee (Apis mellifera L.) colony. Pollinators visited flowers of all crops, with as many as 90 insects min−1 observed. Our study is unique as we measured nectar sugar production, flower density, and insect visitation throughout anthesis for multiple specialty oilseed crops, providing a seasonwide perspective of the flux of nectar resources for pollinators. Adding specialty oilseed crops into current crop rotations could aid in reversing pollinator decline by providing forage resources that are lacking in the current agricultural landscape.
Tập 56 Số 2 - Trang 727-739 - 2016
Heterosis and Combining Ability of CIMMYT's Quality Protein Maize Germplasm: II. Subtropical Information on the combining ability and heterotic patterns of CIMMYT's maize (Zea mays L.) germ plasm is of great value to maize breeders worldwide, for hybrid development. The objective of this study was to determine the heterosis and combining ability of CIMMYT's subtropical quality protein maize (QPM) germplasm, and to identify suitable germplasm for hybrid development. Six QPM gene pools and four QPM populations were used to make a 10‐parent diallei. Parents and the 45 crosses were tested in three environments in Mexico and three in the USA. Highly significant (P < 0.01) differences were observed among entries, parents, and crosses for grain yield, time to silk, plant height, and endosperm hardness in Mexican environments, and for grain yield, ear height, and time to silk in U.S. environments. General combining ability (GCA) effects were highly significant for all traits, while specific combining ability (SCA) effects were nonsignificant (P > 0.05). Population 68 QPM was the highestyielding parent (6.99 Mg ha‐1 ) in Mexican environments, and Pool 31 QPM was the highest yielding (4.65 Mg ha‐1 ) in U.S. environments. The highest‐yielding crosses were Pool 32 QPM × Population 68 QPM (7.05 Mg ha‐1 ) in Mexican and Pool 29 QPM × Population 70 QPM (5.12 Mg ha‐1 ) in U.S. environments. Under Mexican environments, Population 68 QPM and Pool 32 QPM among whites and Population 69 QPM and Pool 34 QPM among yellows were the best general combiners for grain yield. For endosperm hardness, the best combiners were Pool 33 QPM, Population 69 QPM, and Pool 31 QPM, all of which have flint grain type. Under temperate U.S. conditions, the two early‐maturity gene pools (Pool 27 QPM and Pool 29 QPM) and Population 70 QPM were the best combiners for grain yield. For subtropical conditions, Population 68 QPM, Pool 32 QPM, Population 69 QPM, and Pool 34 QPM hold potential for hybrid development. These are hard endosperm opaque‐2 (o2 ) parents (except for Pool 34 QPM, a partially modified parent). For temperate breeding programs in the USA, Pool 27 QPM, Pool 29 QPM, and Population 70 QPM could be used as exotic germplasm sources for introgression into U.S. Corn Belt QPM materials and for developing hard endosperm QPM hybrids.
Tập 33 Số 1 - Trang 51-57 - 1993
Heterosis and Combining Ability of CIMMYT's Quality Protein Maize Germplasm: I. Lowland Tropical CIMMYT has developed a wide array of hard endosperm opaque‐2 (o2 ) maize (Zea mays L.) germplasm, through the combined use of two genetic systems involving the o2 gene for improving protein quality and the genetic modifiers of the o2 locus for improving kernel phenotype and ameliorating other o2 ‐associated defects. The objective of this study was to determine the heterotic patterns and combining ability of tropical quality protein maize (QPM) germplasm, and identify superior germplasm suitable for hybrid development. Ten parents (four QPM pools, five QPM populations, and experimental variety PR 7737) were used in a diallel study in eight environments. Data on grain yield, time to silk, plant height, and endosperm hardness were recorded. General combining ability (GCA) effects were highly significant for all traits; specific combining ability (SCA) effects were signififant for time to silk and plant height. Genotype × environment interactions and their partitions were significant for grain yield and endosperm hardness. Pool 24 QPM was the highest‐yielding parent (6.48 Mg ha‐1 ) and Pool 24 QPM × Population 63 was the highest‐yielding croos (6.56 Mg ha‐1 ) among hard endosperm parents. PR 7737, a soft endosperm opaque‐2, was low yielding as a parent, but performed better in crosses with other hard endosperm parents and showed high heterosis. High‐parent heterosis for grain yield was generally low in all crosses except those involving PR 7737 as a parent. Endosperm hardness ratings were intermediate relative to the parents, suggesting polygenic control. Crosses among white endosperm parents generally performed better than crosses among yellow endosperm parents. Crosses among dents and dent × flints yielded higher than flint crosses, but flint parents and their crosses had a superior endosperm modification. compared with dents. Populations 62, 63, and PR 7737 showed significant positive GCA effects for grain yield; Pool 23 QPM, Pool 25 QPM, and Populations 62, 64, and 65 had significant negative GCA effects for endosperm hardness. Populations 62 and 63 among white endosperm materials and Population 65 among yellow endosperm could be used for initiating hybrid development work. The broad genetic base provides opportunities for developing intrapopulation interline hybrids.
Tập 33 Số 1 - Trang 46-51 - 1993
Heterosis in Population Crosses of Alfalfa<sup>1</sup> A partial diallel cross with 32 parental lines of alfalfa, Medicago sativa L., was evaluated to determine genetic variability and heterosis expressed for forage yield when pest‐resistant, low‐yielding parents were crossed with noninbred, vigorous germplasm. The parental lines included eight half‐sib family seed lines from two commercial cultivars, ‘Apalachee’ and ‘Arc,’ and from two pest‐resistant experimental populations, MSA and MSB. Progenies from the intercross of each of the parental lines were also included in the experiment. Significant mean squares for cultivars from which the parental lines were derived and for lines in cultivars were observed for the intercrosses of the parental lines and for general combining ability. In both cases, the mean square for cultivars was more than 20 times larger than the mean square for lines in cultivars. Significant specific combining ability was not detected. Interactions between genetic effects and years generally were not significant. Crosses had significantly greater yield than the mean of the parental line intercrosses for each of the cultivar combinations. Generally, crosses with lines from MSA or MSB as one of the parents yielded significantly less than crosses between lines from Apalachee and Arc, and crosses between lines from MSA and MSB yielded significantly less than crosses from any other cultivar combination. The intercrosses of parental lines from MSA had greater average yield than those from MSB, but parental lines from MSA had lower combining ability than those from MSB.
Tập 23 Số 1 - Trang 48-50 - 1983
Issues in Diallel Analysis Critical issues in the use of diallel analysis are reviewed. From a statistical point of view the critical issue concerns the choice of a model with fixed or random genotypic effects. From a genetical point of view, two assumptions are critical in attempts to interpret the resuits of diallel analyses. The assumption concerning the independent distribution of genees in the parents is most critical to proper interpretation and seems to be least acceptable in actual practice. The second assumption, that there is no epistasis, may frequently be incorrect. Epistasis affects estimates of general and specific combining ability mean squares, variances, and effects in an unpredictable manner. As an alternative to genetic interpretation, the statistical description provided by dialiel analysis can be used to help answer questions concerning the importance of specific combining ability and the predictability of hybrid performance using general combining ability or parental performance.
Tập 18 Số 4 - Trang 533-536 - 1978
Spectral Water Indices for Assessing Yield in Elite Bread Wheat Genotypes under Well‐Irrigated, Water‐Stressed, and High‐Temperature Conditions ABSTRACT The objective of the present work was to determine the relationship between spectral reflectance indices (SRI) and yield in spring wheat (Triticum aestivum L.) in NW Mexico in three environments (irrigated, water‐stress, and high‐temperature). The SRI were classified into vegetative indices (three indices) and water indices (five indices). The SRI were determined at booting, heading, and grain‐filling in advanced lines of three trials of the International Maize and Wheat Improvement Centre in Mexico (CIMMYT), Elite Spring Wheat Yield Trial (ESWYT), Semi‐Arid Wheat Yield Trial (SAWYT), and High Temperature Wheat Yield Trial (HTWYT). Two water indices (NWI‐1 and NWI‐3) always provided higher correlations with grain yield when heading and grain filling were combined in SAWYT, ESWYT, and HTWYT. Vegetative indices showed inconsistency in their relationship with grain yield. The water indices gave higher genetic correlations and correlated response with grain yield than the vegetative indices in the three trials in all the environments across years. The relationship between yield and canopy temperature determined at grain filling also showed stronger association with yield. The high‐temperature environment showed the strongest associations between SRI and grain yield. The water indices can be used for breeding purposes for selecting high‐yielding lines in well‐irrigated, water‐stressed, and hot environments, and canopy temperature could complement this selection.
Tập 50 Số 1 - Trang 197-214 - 2010