Plant Tiller Research Articles

Identification of a New Rice Low-Tiller Mutant and Association Analyses Based on the SLAF-seq Method

By studying the regulatory mechanism by which rice tillers are controlled, many rice mutants were described as providing important insights into the investigation of tillering control. In this study, we surveyed a new rice mutant produced by ethyl methane sulfonate induction, designated as Oryza sativa low-tiller 1 (oslt1), which had been planted to the fourth generation and proved to stably inherit the low-tillering trait. The statistical analysis of the number of tillers in oslt1 showed that there was a significant lack of tillering in the mutant lines, with the average number being 2.33 as opposed to 8.00 in wild-type plants. The data from a series of crossed populations, including F2 populations produced by selfing of the offspring of oslt1 × ptb and backcross populations of the F1 generation × oslt1, indicated that a single recessive gene controlled the low-tillering trait. To locate the recessive gene, the crossed population in the F2 generation from two parents, oslt1 and Peiai 64, was constructed and the population was used for bulked segregate analysis based on specific locus amplified fragment-sequencing (SLAF-seq) method. The results showed that approximately 100 differential markers were procured by analyzing 7437 polymorphic SLAFs and 1 primary region associated with low-tillering characteristics located on Chr12. In the associated regions, there were 34 candidate genes of 0.24 Mb that might be related to the number of low tillers in oslt1 plants. All of these results are necessary for further fine mapping for this low tillering-related gene. In addition, these identified SLAF-tags will be valuable for marker-assisted selection in rice breeding.

Variability and trait relationships among finger millet accessions in Uganda

Finger millet (Eleusine coracana (L.) Gaertn]) is a vital component in the farming systems of many parts of Uganda with limited information on variability, heritability and trait association in the country. The objective of this study was to assess the variability, heritability and trait association of finger millet to determine the genetic potential for future use in breeding programmes. A total of 100 accessions were evaluated for morpho-agronomic characters in a 10 x 10 lattice design at NaSARRI and Ikulwe in Uganda for two seasons. Analysis of variance revealed mean squares of the genotypes were significant for all the traits, with days to 50% flowering showing the least coefficient of variation and the highest leaf blast severity. Heritability estimates ranged from 7.39% for threshing percentage to 68.4% for head blast severity; whereas values of expected genetic advance varied from 2.00 to 79.9% for threshing percentage and head blast severity, respectively. High heritability and genetic advance estimates were exhibited for head blast severity, head blast incidence, productive tillers plant-1 and grain yield. When the significant correlations were decomposed by path analysis, it revealed that, in determining yield, the most important traits were grain mass head-1, tillering ability and reaction to head blast disease. Overall the result revealed existence of high variability for the traits studied in the finger millet accessions which can be utilised in genetic improvement.Keywords: Eleusine coracana, head blast, heritability

Quantitative Trait Loci Mapping for Tillering-Related Traits in Two Switchgrass Populations.

Plant tillering and related traits are morphologically important components contributing to switchgrass ( L.) biomass yield. The objectives of this study were to estimate broad-sense heritabilities for tillering-related traits, to analyze correlations between biomass yield and the traits, and to identify quantitative trait loci (QTL) for them. A first-generation selfed population of NL94 plant and a hybrid population between NL94 and SL93 plants were field established in a randomized complete block design with three replications in Stillwater and Perkins, OK. Phenotypic data were collected in 2 yr and genotypic data were obtained by genotyping simple-sequence repeat (SSR) markers in the two populations on the basis of two preexisting genetic maps. Plant base size (PBS), plant girth (PG), tillering ability (TA), tiller diameter (TD), and tiller dry weight (TDW) were positively correlated with biomass yield in both populations. Consistently, PBS had the largest correlation coefficients for biomass yield, suggesting its value as an indirect selection criterion for biomass yield. Twenty and 26 QTL for six tillering-related traits were detected in the hybrid and selfed population, respectively. Among the QTL, one on linkage group (LG) 5a between sww-2387/PVCAG-2197/2198 and PVGA-1649/1650 for PBS, PG, and TA and another on LG 2a between sww-2640/sww-2545 and PVCA-765/766 for TD and TDW were stably detected in multiple environments in the two populations. The findings add to the knowledge base regarding the genetics of tillering-related traits that could be used in accelerating the development of high-yielding cultivars through marker-assisted selection.

Nature and magnitude of genetic variability and diversity analysis of Indian turmeric accessions using agro-morphological descriptors

Turmeric, a vegetatively propagated crop, may have restricted variability from which to breed new cultivars. Understanding the genetic variability of a species is crucial for the progress of a genetic breeding program and requires characterization and evaluation of accessions. The objectives of this study were to determine extent of variability, relationships between different agro-morphological traits, and diversity among 25 different accessions of turmeric. The present experiment was conducted at the Vegetable Research Farm, Department of Horticulture, Sam Higginbottom Institute of Agriculture, Technology and Sciences, Allahabad, India during 2008–2009 and 2009–2010. Accessions were arranged in a randomized complete block design with three replications. Significant mean square of accessions for all the traits studied indicates the existence of sufficient genetic variability among the studied accessions. The rhizome yield exhibited highly significant and positive association with plant height, number of leaves plant−1, number of tillers plant−1, weight of rhizomes plant−1, length of primary rhizome, and dry matter recovery. The highest positive direct effect on rhizome yield was exerted by plant height. Multivariate analysis techniques allowed an effective study of genetic divergence and the grouping of the 25 accessions into six clusters. The highest inter-cluster distance was observed between cluster II and IV, accessions from these clusters can be used as potential parents for future breeding programs.

Analysis and simulation of phenotypic plasticity for traits contributing to yield potential in twelve rice genotypes

High-yielding rice varieties (HYV) show strong phenotypic plasticity, notably in compensatory tiller production and panicle size. In a precursor study on the high-tillering cv. IR72 we showed that the plasticity is adaptive by enabling yield stability across different stand densities, and we presented and validated the functional-structural crop model SAMARA, developed for the study of phenotypic plasticity. The present study analyses the phenotypic plasticity of high and low tillering plant types. Twelve contrasting, high-yielding irrigated rice genotypes were studied for the plasticity of traits contributing to grain yield under different season/site environments and stand densities in the Philippines. For the density factor, sequentially developing yield components along phenology, beginning with tillering, showed decreasing plasticity, indicating progressive adjustment to the initial stand density. For the site/season factor (climate), tillering was less plastic and panicle size and grain filling ratio provided for the strongest adjustments. Large plasticity was observed also for LAI and little plasticity for SLA and leaf morphology, particularly blade width. Genotypes differed strongly in organ size vs. number (leaves, panicles), representing organ “number” or “size” plant types. Up to 10Mgha−1 grain yield were observed for both extreme types. The plasticity of panicle size was caused by variation in spikelet number and not kernel weight. All genotypes were able to fully adjust yield components to differential plant stand density, resulting in unchanged yield. However, between environments, genotypes having greatest maximal yields and those having stable (but on average smaller) yields showed different patterns of phenotypic plasticity for yield component and plant morphology traits. The SAMARA model was calibrated for five genotypes showing contrasting morphology and plasticity. It was able to predict most of the genotypes’ variation in morphological and yield component traits. Future opportunities to predict improved rice ideotypes for changing environments and cultural practices through combined field experimentation and modelling are discussed.

PRIMARY PRODUCTION VARIABLES OF BRACHIARIA GRASS CULTIVARS IN KENYA DRY LANDS

<p>The study was conducted to evaluate the primary production variables of <em>Brachiaria</em> grass cultivars in semi arid regions of Eastern Kenya. <em>Brachiaria</em> cultivars <em>B. decumbens</em> cv. Basilisk, <em>Brachiaria</em> hybrid Mulato II, four <em>Brachiaria brizantha</em> cultivars Marandu, Xaraes, Piata, MG4 and <em>Brachiaria humidicola</em> cv Llanero were assessed with reference to their field establishment and growth rates. <em>Chloris gayana</em> cv. KATR3 and <em>P. pupureum</em> cv. Kakamega I were included as controls. Plant numbers, heights, spread, plant tiller number and plant cover were monitored for the initial 16 weeks following seedling emergence. A standardization cut was done on all the plots at week 16 and dry matter yields determined. All growth parameters measured varied significantly (<em>p</em><0.05) among the cultivars. <em>Chloris gayana</em> cv. KATR3 recorded the highest plant numbers (48plants/m<sup>2</sup>). Llanero recorded highest plant spread (146.9 cm) and tiller number (31tillers/plant). Napier had the highest plant height (103.8cm), cover (94.9%) and average dry matter yields (5430kg /ha). The results demonstrate that <em>Brachiaria</em> grasses are capable of establishing themselves in the semi arid regions of Eastern Kenya. It is recommended that the experiment be conducted for a longer period of time to determine their growth capacity during dry spells and pests and diseases that can hinder establishment and production.</p><p>The results demonstrate that <em>Brachiaria</em> grasses are capable of establishing themselves in the semi arid regions of Eastern Kenya. It is recommended that the experiment be conducted for a longer period of time to determine their growth capacity during dry spells and pests and diseases that can hinder establishment and production</p>

Production and Quality in Dwarf Napier Grass Pasture Fertilized by Digested Effluent of Manure under Two-Years of Dairy Cow-Grazing in Warm Regions of Japan

Dwarf Napier grass (Pennisetum purpureum) pasture is suitable for beef cow grazing in warm regions of Japan, while it is not assessed for the suitability by a herd of dairy cows in the region. This study was conducted to determine the effects of Digested Effluent (DE) application on herbage yield and quality, Herbage Consumption (HC) and Dry Matter Intake (DMI) under a paddock scale of rotational grazing by a herd of dairy cows on dwarf Napier grass pasture in southern Kyushu, Japan for two years in 2007 and 2008. Plant growth attributes, such as plant height, tiller number and herbage mass and HC increased consistently from the first to the second or third grazing cycle in the two years. Pre-grazing herbage mass was averaged at 176 and 193 g m-2 in Chemical Fertilizer (CF) and DE treatments, respectively and HC and DMI did not differ between the two treatments. Overwintering ability was almost perfect in Miyazaki, judged by 97.1% of regrown plants in May 2008. Thus, dwarf Napier grass pasture fertilized with liquid DE can be utilized by dairy cow grazing as the same with CF fertilization, where DMI was averaged at 4.4 kg dry matter head-1 day-1 for 3 summer months in the two years.

Effect of cultivar and seed rate on weed infestation and crop performance of wheat

An experiment was carried out at the Agronomy Field laboratory of Bangladesh Agricultural University, Mymensingh during the period from November 2014 to March 2015 to study the effect of cultivar and seed rate on weed infestation and crop performance of wheat. Three wheat cultivars viz. BARI Gam 24, BARI Gam 25 and BARI Gam 26 and five seed rates viz. 80, 90, 100, 110 and 120 kg ha-1 were considered as the experimental treatment. The experiment was carried out in Randomized Complete Block Design with three replications. The cultivar and seed rate were significantly influenced on weed infestation and crop performance of wheat. The dry weight of weeds in cultivar BARI Gam 26 was the lowest (9.24 g m-2) compared to other cultivars. The lowest dry weight of weed was recorded in the seed rate of 120 kg ha-1 (7.57 g m-2) and the highest one (16.14 g m-2) was produced in seed rate of 80 kg ha-1. The highest plant height (93.27 cm), number of effective tillers plant-1 (3.69) and 1000-grain weight (44.51g) were produced in BARI Gam 25. The highest number of spikelet spike-1 (18.12) and grains spike-1 (34.51) were produced by BARI Gam 26. BARI Gam 26 produced the highest grain yield (2.51 t ha-1) which was as good as BARI Gam 25 (2.48 t ha-1). BARI Gam 26 produced the highest grain yield with 100 kg seed rate and also a good competitor against weeds. Seed rate was a reliable factor where increasing seed rate reduced the weed dry weight production. In conclusion, cultivation of BARI Gam 26 @100 kg ha-1 seeds may be cultivated for higher grain yield.Progressive Agriculture 27 (1): 20-26, 2016

Genet ic Variability and Divergence Studies for Gall Midge Resistance and Yield Components in Rice (Oryza sativa L.)

Eighteen rice genotypes were evaluated for studying genetic parameters and genetic divergence for yield contributing characters and gall midge resistance at Regional Agricultural Research Station, Jagtial, Telangana. Analysis of variance revealed the presence of significant variability in experimental material for all the traits under study. Heritability estimates and genetic advance values indicated that percent of galls, effective bearing tillers plant−1, 1000 grain weight and number of grains panicle−1 were predominantly governed by additive genes which could be improved through proper selection in desirable direction, whereas, non additive genes played dominant role in the inheritance of days to 50% flowering, plant height and panicle length which could be improved through heterosis breeding. Mahalanobis D2 analysis distributed 18 genotypes into three clusters with cluster I containing maximum number of genotypes (14). Maximum inter cluster distance (10.48) was observed between cluster II and cluster III indicating wider genetic diversity, hence, crosses involving parents belonging to these clusters likely to produce wide variability and transgressive segregants with high heterotic effects. Genotypes JGL 19607, JGL 21820, JGL 3844 (cluster II) and JGL 23745 (cluster III) exhibited least gall midge incidence which could be utilized as parents in developing gall midge resistance genotypes. 1000 grain weight and days to 50% flowering were contributed maximum (75.16%) to the total divergence which could be given due importance during hybridization and selection in segregating populations.

Silicon fertilization and soil water tensions on rice development and yield

ABSTRACT The cultivation of upland rice (Oryza sativa) in Brazil occurs mainly in the Cerrado, a region with adverse weather conditions. The use of silicon in its cultivation becomes important, since this nutrient provides higher rigidity, lower transpiration and higher resistance to dry spells in rice plants. The objective of the present study was to evaluate the effect of silicon fertilization and soil water tensions on upland rice development and yield in a Cerrado Oxisol. A 5 x 5 fractionated factorial with five soil water tensions (0, 15, 30, 45 and 60 kPa) and five silicon doses (0, 120, 240, 480 and 960 mg dm-3) was used, which were distributed in a randomized block design, with four replicates. Plant height, number of tillers, number of panicles, number of grains per panicle, numbers of full and empty grains and percentage of empty grains were evaluated. Silicon fertilization promotes increased tillering in rice plants at the dose of 960 mg dm-3. The numbers of tillers and panicles decreased with the application of silicon up to the doses of 460 and 490 mg dm-3, respectively. The increase in soil water tensions reduced plant height and the number of full grains, and increased the percentage of empty grains of upland rice.

Occurrence of Viruses and Associated Grain Yields of Paired Symptomatic and Nonsymptomatic Tillers in Kansas Winter Wheat Fields.

Vector-borne virus diseases of wheat are recurrent in nature and pose significant threats to crop production worldwide. In the spring of 2011 and 2012, a state-wide sampling survey of multiple commercial field sites and university-managed Kansas Agricultural Experiment Station variety performance trial locations spanning all nine crop-reporting regions of the state was conducted to determine the occurrence of Barley yellow dwarf virus-PAV (BYDV-PAV), Cereal yellow dwarf virus-RPV, Wheat streak mosaic virus (WSMV), High plains virus, Soilborne wheat mosaic virus, and Wheat spindle streak mosaic virus using enzyme-linked immunosorbent assays (ELISA). As a means of directly coupling tiller infection status with tiller grain yield, multiple pairs of symptomatic and nonsymptomatic plants were selected and individual tillers were tagged for virus species and grain yield determination at the variety performance trial locations. BYDV-PAV and WSMV were the two most prevalent species across the state, often co-occurring within location. Of those BYDV-PAV- or WSMV-positive tillers, 22% and 19%, respectively, were nonsymptomatic, a finding that underscores the importance of sampling criteria to more accurately assess virus occurrence in winter wheat fields. Symptomatic tillers that tested positive for BYDV-PAV produced significantly lower grain yields compared with ELISA-negative tillers in both seasons, as did WSMV-positive tillers in 2012. Nonsymptomatic tillers that tested positive for either of the two viruses in 2011 produced significantly lower grain yields than tillers from nonsymptomatic, ELISA-negative plants, an indication that these tillers were physiologically compromised in the absence of virus-associated symptoms. Overall, the virus survey and tagged paired-tiller sampling strategy revealed effects of virus infection on grain yield of individual tillers of plants grown under field conditions and may provide a complementary approach toward future estimates of the impact of virus incidence on crop health in Kansas.

Effect of split application of nitrogen on performance of wheat (Triticum aestivum L.)

A field experiment was conducted at farmer field of Katihar district during two consecutive years of 2012-13 and 2013-14 to study the yield of wheat as influenced by split application of nitrogen. The soil is non-calcareous light gray in colour flood plain belongs to the alluvial gangetic plain (Agro climatic zone II). The study was done in Randomized Block Design with four treatments and ten replications with HD 2733 wheat variety to evaluate the observation regarding growth attributes and yield components of individual plant parameters were recorded from randomly selected plants in each plot. The evaluated traits were plant population (m -2 ), plant height (cm), bearing tillers plant -1 (no.), non-bearing tillers plant -1 (no.), spikelets spike -1 (no.), fertile spikelets spike -1 (no.) non-fertile spikelets spike -1 (no.), 1000-seed weight (g), seed yield (t ha -1 ) and straw yield (t ha -1 ). Results indicated that the use of three split N applications increased all growth and yield attributes. The best N split strategy corresponded to three N splits: at planting, crown root initiation (CRI), and panicle initiation (PI) stages.

Effect of two whole-crop rice (Oryza sativa L.) cultivars on methane emission and Cu and Zn uptake in a paddy field fertilized with biogas slurry

ABSTRACTA field experiment was carried out to evaluate the effect of two whole-crop rice (Oryza sativa L.) cultivars, TULT and Takanari, on methane (CH4) emission in a paddy field fertilized with biogas slurry (BS) at rates of 0 (NF), 100 (BS100) and 300 (BS300) kg nitrogen (N) ha−1, in comparison with chemical fertilizer CF100 (100 kg N ha−1). Takanari produced significantly higher biomass (P < 0.001) than TULT and showed significantly (P < 0.01) lower CH4 emission than TULT. BS applications caused higher CH4 emission (52 ± 27 and 80 ± 19 g m−2 in BS100 and BS300, respectively) than did CF100 (42 ± 18 g m−2) and NF (28 ± 10 g m−2) in TULT. In contrast, there was no significant difference in CH4 emission in Takanari among the treatments (26 ± 2, 26 ± 2, 32 ± 4, 29 ± 8 g m−2 in NF, CF100, BS100 and BS300, respectively). Methane oxidizing bacteria (MOB) showed significantly (P < 0.05) higher populations in Takanari than in TULT at harvest, which might be due to the higher root biomass (10.3 ± 2.2 g hill−1) in Takanari than in TULT (8.9 ± 1.8 g hill−1). MOB was significantly correlated with tiller number (R2 = 0.176*) and plant biomass (R2 = 0.242*). BS application showed higher copper (Cu) uptake in Takanari while it was not high in TULT. In contrast, it showed no difference in zinc (Zn) uptake in both varieties. Uptake of Cu was not different between the two varieties, while uptake of Zn in the grain was higher in TULT than in Takanari. The present study suggests that CH4 emission deriving from BS application in paddy field can be mitigated by selecting an appropriate cultivar, like Takanari. However, care should be taken for heavy metal uptake in selecting cultivars.

Correlation and Regression Analysis for Yield Traits in Wheat (&amp;lt;i&amp;gt;Triticum aestivum&amp;lt;/i&amp;gt; L.) Genotypes

The present research work was carried out at Southern Wheat Research Station, Tandojam during the growing season 2013-14 in order to work out correlation and regression analysis for yield traits in wheat genotypes. The experiment was laid out in a Randomized Complete Block Design with three replications. Eight bread wheat genotypes such as Mehran, Sarsabz, TJ-83, SKD-1, Inqlab, A. Sattar, Sehar and Sassui were used to examine correlation and regression. Seven traits, viz.; plant height, tillers plant-1, spike length, spikelet’s spike-1, grains spike-1, seed index and grain yield plant-1 were studied. The analysis of variance revealed significant differences among the genotypes for plant height, tillers plant-1, spike length, spikelet’s spike-1, grains spike-1, seed index and grain yield plant-1. Based on mean performance, variety Sarsabz gave maximum plant height (95.46), produced maximum tillers plant-1 (4.40), gave more grain spike-1 (63.13), TJ-83 gave highest seed index (47.260), and was next ranker in spike length-1 (12.07), spikelet’s spike-1 (19.13), grains spike-1 (59.86), and grain yield plant-1 (9.86) among the genotypes. The phenotypic correlations revealed that tillers plant-1 and grains spike-1 were highly positively associated; hence these yield components can be used as reliable selection criteria to improve grain yield in wheat. Thus estimation of correlation and regression analysis among yield and yield components may provide effective selection criteria to improve wheat grain yield. The results from correlation and regression of plant height indicated significantly positive association with spikelet’s spike-1, tillers plant-1 and grains spike-1 which revealed that increase in plant height will cause corresponding increase in associated traits.

Effect of Different Levels of Phosphorus and Method of Application on the Growth and Yield of Wheat

An experiment was conducted to evaluate the productivity of wheat under different levels of phosphorus and method of application at Department of Agronomy, Sindh Agriculture University, Tandojam. Experiment was laid out in a RCBD (factorial) with three replications. The treatments were four phosphorus levels (P1 = 0 Kg?ha–1 + Recommended Nitrogen, P2 = 30 Kg?ha–1 + Recommended Nitrogen, P3 = 60 Kg?ha–1 + Recommended Nitrogen and P4 = 90 Kg?ha–1 + Recommended Nitrogen) and two placement methods (A1 = Drilling method and A2 = Broadcast method). The statistical analysis of phosphorus levels and placement exhibited significant differences to the maturity days, plant height, tiller production, spike length, grains per spike, seed index, harvest index and grain yield ha–1. However, the interactions of P levels and placement in all crop characters were non-significant except the grain yield/ha–1. The results revealed that application of 90 kg P ha–1 prolonged 143 days for maturity, taller plants (100.16 cm), more tiller plant–1 (13.50), lengthy spikes (12.83 cm), more grains spike–1 (51.33), heavier seed index (48.16 g), better harvest index (50.82%) and satisfactory grain yield (4240.50 Kg?ha–1). The unit increase in grain yield was positively correlated with the increased values of observed crop parameters by extending the values of maturity r = 0.85, plant height r = 0.94, tillers plant r = 0.96, spike length r = 0.95, grains spik–1 r = 0.97, seed index r = 0.95 and harvest index r = 0.97. It was concluded that 90 kg P ha–1 was superior level of phosphorus if, applied with seed drilling for obtaining satisfactory grain yield of wheat crop.

Foliar application of calcium and boron improves the spike fertily and yield of wheat

Foliar applications of calcium (Ca) and boron (B) could improve the fertilization of flowers and enhance the wheat yield. The effects of foliar spray of Ca and B on plant growth, grain yield and yield components of wheat were investigated in this study. Treatments consisted of 0, 1.8, 3.6, and 7.2 L ha –1 application of chelated fertilizer containing 125 g L –1 of Ca and 6 g L –1 of B ( Omega Cabor II ® ), divided into two spray, the first one at tillering and the second at early bloom. The results revealed that foliar spray of Ca and B did not affect the stem diameter, peduncle length, spike length, hectoliter weight and thousand-grain mass of wheat. Maximum plant height and flag leaf insertion height was recorded with 4.0 L ha –1 application of foliar fertilizer (4% increase over control). The 7.2 L ha –1 application of foliar fertilizer increased significantly the number of spikelets per spike (9%), number of grains per spike (24%), grain mass per spike (28%), spike mass (14%), number of spikes m –2 (32%) and grain yield (30%) compared to the control. Foliar application of Ca and B improves growth, fertilization of flowers and the number of fertile tillers of wheat plants resulting in higher grain yield.

Physiological and biochemical responses in rice (Oryza sativaL.) to high temperature: A review

Rice is the staple food crop and is the livelihood for most of the people across the globe. Keeping the present climate change scenario in view, there is a severe threat due to rise in temperature that can affect rice yield potential. Heat stress is one of the major abiotic stresses hampering the growth of rice. Temperature at every growth stage plays a critical role in deciding the rice yields. The major effects of heat stress in rice on its morphoagronomical parameters include reduced germination, poor seedling growth, reduction in plant height and tillering, reduction in number of pollen grains, poor anther dehiscence, increased sterility, reduced grain filling and poor grain quality that ultimately lead to yield reduction. From the physiological point of view, there is an inhibition of photosynthesis and related gas exchange traits, reduction in chlorophyll content and other pigments, reduction in chlorophyll fluorescence (Fv/Fm), reduction in cell membrane thermostability as well as an imbalance between photosynthesis and respiration. Biochemically, there is an increase in accumulation of osmoprotectants (praline and glycine betaine), increase in activity of antioxidants and increase in hormone accumulation (abscisic acid and ethylene). A complete understanding of mechanisms conferring thermotolerance and identification of genotypes possessing tolerance is the pre-requisite.

The yield of spring barley in the brown soils of the Nizhnee Povolzh'e region

The results of small (20-22 cm) and relatively deep main processing of the soil (27-30 cm) and variable rate application depth of arable horizon of doses of mineral nutrition (N and P2O5) on yield of spring barley. It is established that ploughing soil up to 30 cm (pillars of Cibima) with in-corporation at the same depth easy phosphorus-rhenium increases the biological activity of the soil microflora involved in the proposal of cellulose substrates is a means of increasing the fertility of light chestnut soil, which is especially important for rainfed conditions. The average crop capacity in the shallow plowing is 2 t/ha and was lower at 15% compared to Varian, where he held a deep subsurface tillage. By years of research sum-total biological activity in the deep subsurface treat-ment amounted to 930 mg of amino acids per gram of leaf, which is higher by 26% the variant with shallow plowing. Compared to shallow ploughing (option 1) at subsurface relatively deep processing of crude soil (option 2) there is greater accumulation of productive moisture in a meter layer. In the period of tillering of plants at average moisture reserves in option 2 is higher by 16% than in option 1 and constitute a 147 mm. In phase trubavina-earing and full maturity of the spring-barley the difference between the productive moisture content increases to between 20 and 33% in the direction of no-till deep processing. Relatively high soil moisture (a consequence of the method of tillage) contributed to a more rapid transition of phosphates in the horizon of 25-30 cm and nitrate in the layer 10-15 cm in available forms of nutrients for soil microorganisms. It is revealed that the application rate of nitrogen and phosphorus should be linked with the main processing of the soil, and the peculiarities of development of the root system of cultivated crops.

English

A greenhouse pot experiment was carried out during November 2013 to May 2014. Winter wheat grains (Triticum aestivum L.), cultivars Abu-Ghureb and Cham6 were used to investigate the effect of soaking seeds in 300ppm of benzyl adenine (BA) or daminozide solutions for 6 hours before sowing vegetative, yield components, leaf chlorophylls and some chemical constituents of seeds. BA treatment led to significant increases in tiller number plant-1, chlorophyll b, P, dry gluten, N and protein contents of seeds. It also led to significant decreases in number of leaves plant-1. In addition, the number of tillers plant-1, shoots dry weight plant-1, P, N and protein contents of seeds were increased by daminozide treatment, but this caused a significant decrease in the plant height, number of leaves plant-1 and flag leaf area. Number of grains plant-1, weight of 1000 grains and grains yield were significantly increased by both treatments. Cultivar variability was noted for some tested parameters. The tall, N, P content and protein content of Abu-Ghureb cultivar were higher significantly than Sham6. The case was opposite with number of leaves plant-1, flag leaf area, shoots dry weight plant-1, spike length and grain number plant-1.

Acúmulo de forragem e características morfogênicas e estruturais de Axonopus aureus no cerrado de Roraima

800x600 Normal 0 21 false false false PT-BR X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:Tabela normal; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:Calibri,sans-serif;} The effects of cutting plant age (21, 28, 35, 42, 49, 56, 63 and 70 days) on dry matter (DM) yield, and morphogenetic and structural characteristics of Axonopus aureus , during rainy season, were evaluated under natural field conditions. The experimental design was a completely randomized, with three replications. Evaluations were carried out during the period of June to August 2009. DM yield, absolute growth rate (AGR), number of tillers plant -1 , number of leafs plant -1 , leaf area, leaf senescence and elongation rates and blade length increased consistently with growth stage. The relations between DM yield and AGR with cutting plants age were described by the quadratic regression model. The maximum DM yield and forage production rate performance were estimated at 62.7 and 49.4 days of regrowth. The crop growth and relative growth rates, tiller and leaf appearance rates were inversely proportional to cutting plant age. These data suggest that cutting at 49 to 56 days were optimal for obtain maximum dry matter yields and improved the grass morphogenetic and structural characteristics. Normal 0 21 false false false PT-BR X-NONE X-NONE MicrosoftInternetExplorer4 st1\:*{behavior:url(#ieooui) } /* Style Definitions */ table.MsoNormalTable {mso-style-name:Tabela normal; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:Calibri,sans-serif;}