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Progenies of a Design II [Comstock and Robinson (1948)] using random S 1 lines from an exotic population of corn (Zea mays L.) were evaluated in a randomized incomplete block design with two replications at two plant-population densities (1 7,222 plants/ha and 68,888 plants/ha) in 1970 and 1971, at Lincoln, Nebraska. Five traits were studied i.e. grain weight, number of ears, days to flower, plant height and ear height.Under both densities the estimates of additive genetic variance were much larger than those of dominance genetic variance for all traits. The ratio of dominance to additive genetic variance estimates was less than 0.5 suggesting that for the majority of loci controlling the traits, partial to complete dominance is likely.The estimates of additive genetic x year interaction variance were high and significantly different from zero under both densities, indicating that estimates of additive genetic variance in this population obtained from experiments conducted in only one year may be seriously biased. The estimates of dominance genetic x year interaction variance were not significant and most of them were negative.Under both densities high genetic inter-relationships were indicated between grain weight and number of ears, days to flower and plant height, days to flower and ear height, and plant height and ear height.Even though there was a large difference between the two densities used in the study, the differences between the estimates of genetic parameters were not significant in all cases.The sample size of S 1 plants representing each S0 parent in the crossing nursery used in the present study (11.75) caused a small upward bias in the estimates of additive genetic variance, but it caused an upward bias in the estimates of dominance genetic variance of 6-7% of the total genetic variance.It is suggested that a trait such as grain weight should be expressed on a unit area basis when genetic parameters (except for correlation and the ratio between two values) obtained from experiments with different plant-population densities are to be compared.

Rice plants were enclosed in mylar film in the field and given CO2 enrichment at five stages of panicle development and grain filling. CO2 enrichment for 33 days before flowering increased grain yield by 30% over the control. This increase could be largely attributed to increased grain number and increased grain weight. Nine or 10 days enrichment at rachis-branch differentiation stage or spikelet differentiation stage increased grain yield by 10% ; this increase largely results from increased grain number. Two-week enrichment from reduction division to flowering had no over-all effects on grain yields. Thirty days enrichment after flowering increased grain yield by 10% over the control as a result of increasing grain weight and filled grain percentage. This experiment demonstrated that grain number per unit land area is more limiting to grain yield than grain filling.

The main objetive of this study was demostrated the interrelationships between yield and its component on spring wheat by mean the path-coefficient analysis. The following characters were measured: grain yield per plant, number of grains per spike, 1000-grain weights, heading date and plant height.The results indicated that only number of spikes and heading date were shown to be positively correlated, r = 0.861** and r = 0.684**, respectively, with grain , yield.Through the path-coefficient analysis it was demostrated that the direct effects on yield were positive and hight in the following characters, considered as the primary yield components: number of spikes (P = 1.0344), grains per spike (P = 0.7104) and grain weight (P = 0.7110). In the case of heading date and plant height, considered as secondary components, the effects on yield were low (P = - 0,1013 and P = 0.1513, respectively).The effects of yield components on yield were disturbed by the use of simple correlation coefficients as a. mean to analise the degree of association between characters., Se investigó las interrelaciones y su efecto sobre el rendimiento de los factores considerados como componentes del rendimiento en trigo de primavera. Los caracteres evaluados fueron rendimiento de grano por planta, número de espigas por planta, número de granos por espiga, peso de 1000 granos, precocidad (días de siembra a espigadura) y altura de planta adulta.Los resultados mostraron que el rendimiento sólo estuvo correlacionado en forma positiva y significativa al nivel de 0,01, con número de espigas (r = 0,861) y precocidad (r = 0,684).A través del análisis de causa y efecto se demostró que los efectos directos sobre el rendimiento fueron positivos y altos de los siguientes caracteres, considerados como componentes principales: número de espigas (P = 1,0344), granos por espiga (P = 0,7104) y peso de los granos (P = 0,7110). En el caso de la precosidad y altura de planta, considerados como componentes secundarios, fueron bajos, P = - 0,1013 y P = 0,1513, respectivamente.El uso de las correlaciones simples, como un medio de analizar el grado de asociación entre los caracteres, alteró los efectos de los componentes sobre el rendimiento.

Four exotic and four indigenous strains of barley were used for making diallel crosses. The sets of parents and crosses making full, half and quarter diallel were analysed in a randomized block design for plant height, number of effective tillers, ear length, grain yield per plant, 100 grain weight and number of grains per ear.The three alternatives of diallel were similar with respect to the estimates of degree of dominance, general combining ability and specific combining ability, indicating that all these three methods of diallel were equally efficient. However, as the number of entries are minimum in quarter diallel, it would be economical in terms of cost, time and labour to estimate genetic parameters by this method. Average degree of dominance was found in the range of overdominance. The ranking of parents on the basis of their array mean was similar to the ranking based on gca effects. Similarly, the ranking of crosses on the basis of per se performance was similar to the ranking based on sca effects. This suggests that the selection of best general combiner or best cross combinations may be easier and more effective through array mean for per se performance rather than through high gca and sea effects, respectively. From among 56 crosses, IB-226 X X C-164 was the one which showed superiority for maximum number of characters followed by AB-12/59 X PTS-57. High sea effect for plant height, ear length, grain yield, 100 grain weight and number of grains per ear was the result of cross between parents having high X low general combining ability, indicating additive X dominance type of gene interaction. For number of effective tillers, high sca was produced by low x low general combiners, indicating dominance x dominance gene interaction.

Two standard Wheat cultivars (‘Gamenya’ and ‘Triple Dirk’) and three semidwarf wheats (‘Matipo’, ‘Karamu’, and ‘Ciona-S’) were drilled at 77, 150, 216, and 284 kg/ha in the spring. Production and survival of tillers on permanently tagged plants were recorded at weekly intervals, and the number and weight of grains on the main stem and on the first, second, and remaining tillers of these plants were determined before the crop was harvested. Grain yield of the semidwarf wheats was 16% higher on average than that of the standard wheats, with no indication of any variety × sowing rate interactions for grain yield or any of its primary components (ears per unit area, grains per ear, and weight per grain). The tillering pattern of the semidwarf wheats was directly comparable with that of the standard wheats, and the yield superiority of the semidwarfs was largely due to their consistent advantage in total grain weight per ear. The ears on the main stems contributed 44% of grain yield at the lowest sowi...

The effect of selection for two-seeded pods in diploid and tetraploid populations and the effect of chromosome doubling on two-seededness were studied. The material obtained was examined to find out how important two-seeded pods are for seed set, grain weight and seed yield.

The experiment was performed to find out the effect of irregular disposition of drill-seeded rice plants upon yield in direct sowing culture. Row of 1 m length was divided into ten equal sections (10 cm row) and number of plants in them was varied. Co-efficient of variation (cv) of number of plants in 10 cm row was used as the index of irregular disposition and five plots of cv 0 %, 30 %, 60 %, 100 %, and 150 %, were established. 1. The more irregular disposition of plants was, the more decrease in grain weight (per unit area) was. It's degree was more remarkable in Fujiminori (early maturing and panicle type variety) than in Manryo (medium maturing and medium tiller type variety). 2. Decrease of grain weight was caused by that of number of panicles (per unit area). In Fujiminori, number of panicles decreased according as irregularity in disposition of plants increased. grain weight per panicle being remained unchanged. Therefore grain weight decreased in proportion to increase in irregularity of plant disposition. In Manryo, however, grain weight per panicle increased though number of panicles decreased. Accordingly decrease of grain weight compared with the plot of cv 0 % was not observed in plots of cv 30∼100 %. 3. In Fujiminori, decrease of grain weight with irregular disposition of plants was more marked in the case of low seeding density than in that of high one. In Manryo, however, the difference of the effect of irregular disposition on grain weight caused by different spacing densities was not clear.

Rice plants in the field were enclosed in chambers covered with mylar film and subjected to CO2 enrichment for 30 days before or after flowering. The CO2 enrichment was intended to increase grain number (sink size) befiore flowering, and to increase photosynthesis of a canopy (source) after flowering. The CO2 enrichment before flowering increased grain number per unit land area and grain weight. The enrichment after flowering did not affect grain number but increased filled-grain percentage and grain weight. As a result, both treatments increased grain yield. Analysis of yield components indicates that a major factor responsible for the yield differences is grain number. It was also shown that the increase in yield was directly proportional to the dry matter increase after panicle initiation. The CO2 enrichment before flowering increased grain number per unit land area and grain weight. The enrichment after flowering did not affect grain number but increased filled-grain percentage and grain weig...

SUMMARY A field trial of autumn-sown rye cv. Lovaszpatonai subject to natural infection with Cercosporella herpotrichoides showed that eyespot, in the absence of lodging, was significantly correlated with reduced grain size and 1,000 grain weight but not with total yield in weight of grain. No seed treatment affected total yield although benomyl significantly increased fertile tiller number, increased the percentage of lesion-free tillers in April, and by July, compared with the control, had reduced the number with eyespot lesions by 38 per cent. In laboratory experiments organomercury and a combined treatment of organomercury plus chlormequat protected seedlings from attack by seedborne fungi and in the field trial these treatments also increased the percentage of lesion-free tillers in April but did not affect the numbers with eyespot in July.

SUMMARY Frequent spraying with fungicides gave a fairly good control of glume blotch (Septoria nodorum) in winter wheat and increased the persistence of green leaf tissue. Spraying resulted in substantial increases in yield which related well to the degree of disease control achieved; the increase over unsprayed ranged from 18 to 43 per cent, depending on the fungicide used. The whole of the yield increase could be accounted for in terms of 1,000 grain weight.

Generally in indicas, compared with japonicas the carbohydrates concent in plant is less at heading time, number of spikelets per panicle is more, ripening period is short, therefore, competiton for absorbing carbohydrates among kernels on panicle is very severe and inferior kernels become sterile, abortive and opaque easily. By top dressiag in indicas carbohydrates content at heading stage decreases and number of spikelets per panicle, especially on secondry branches increases, then the competition among kernels becomes more severe causing the inferior kernels stop their growth and bdcome sterile, abortive and opaque kernels. More over grain weight of normal kernel is also decreased. In japonicas, carbohydrates content scarcely decreases and increase in number of flowers per panicle is small, which causes the ripening slightly deteriorate, and on the other hand the grain weight shows a slight increase. As a result in two varieties of japonica, grain yield per panicle is increased. Grain yield of Dular remains unchanged, where as, a slight decrease and rather decrease is obtained in case of Bluebonent and Te-Tep respectively. Karalath, which is thought a most unadaptable variety to heavy manuring decreases to 84%. Moreover, by heavy manuring, increase of panicles per plant is conslderable in japonicas, but it is small in indicas, so heavy manuring obviously causes increase of the yields in japo-nicas and scarcely increases rather decreases in indica varieties. In the light of these points it could be recommended that increase of yields can be obtained with the additional nitrogen fertilizer, when depending upon the nitrogen application the number of panicles per plant is increased and the flowers per panicle, particulary the flowers of secondary branches are kept almost constant. In varieties having such characteristics, the ripening does not deteriorate and high yields of good quality are expected. (Kinmaze and Towada) Besides this, with high nitrogen when panicle increases in size, branches in(:rease in number but the number of flowers on secondary branches does not increase or increase nominally the ripening is not severely worsened. This characteristic is also suitable for heavy manuring. This trend is observed in Bluebonnet.

SUMMARY A partial control of Septoria diseases was obtained with frequent appl.ications of tank-mix zineb. In the control Pl.ots traces of glume blotch (S. nodorwn) and a moderate attack of leaf disease (mainly S. tritici) occurred, but the full spray programme increased yields by about 35 per cent. The disease did not develop until after ear emergence and the increased yields were due to an increase in grain weight. When only two sprays were applied, after ear emergence, the yield increase was about 10 per cent.

Summary The respiration rate of attached ears of eight varieties of wheat was measured during grain development by means of an infrared gasanalyzer. The rates increased rapidly after flowering and reached a maximum value 8–10 days later. In the following period ear respiration decreased continuously. Dry matter increase of the grains was not synchronous to the time course of the ear respiration rates. During the maximum stage of respiration dry matter increase of grains is still low. Respiration rates of fertile and pollensterile ears of the same variety were compared during the whole phase of grain development. Their were also measured the rates of intact ears and ears deprived of kernels. From the results it was concluded, that the grains contribute about 40 % to the respiration of the whole ear. Comparing the theoretical value of respiration, necessary for biosynthesis of grain dry matter, it is concluded that the contribution of grain respiration to the respiration of the whole ear varies between 30 and 50 % in the genotypes investigated. There are differences between genotypes in relation to the coefficient, calculated from all respired CO 2 in the grain filling stage and the grain weight per ear.

This research was carried out in experimental field of Field Crops Department of Agricultural Faculty of Namik Kemal University in randomized split block design with three replications per treatment during 2004-2005 and 2005-2006. The objective of this study was to find out the contribution rates of awn, flag leaf, 1 st upper leaf blade, 2 nd upper leaf blade and other leaf blades to main yield components in three durum wheat cultivars (cv. Kiziltan-91, Kunduru-1149, and Yelken-2000). The results of this experiment showed that removal of awn, flag leaf, 1 st upper leaf blade, 2 nd upper leaf blade, and other leaf blades reduced significantly spike weight, number of grains per spike, grain weight per spike, and 1000-grain weight except the number of spikelets per spike. It was concluded that the organs play an important role in grain yield in durum wheat during grain filling stage. Keywords: Photosynthetic organs; yield components; durum wheat. DOI: http://dx.doi.org/10.3329/bjar.v36i1.9224 BJAR 2011; 36(1): 1-12

SummarySeveral alternative statistical approaches to the analysis of genotype-environment interactions are summarized, and their inter-relationships are presented mathematically and graphically. An experiment was designed to test the ability of these analyses to satisfactorily describe genotype-environment interactions and to locate genotypes causing or contributing significantly to such interactions in a situation where environments differed in only one factor, i.e. soil nitrogen status.Twenty-five lines of wheat were grown at each of 5 levels of applied nitrogen (0–270 kg N/ha) in a sandy, nitrogen-deficient soil, and their grain yields and yield components (ears per unit area, grains per ear, weight per grain) were determined. Designating the nitrogen levels as ‘environments’, linear yield responses, and deviations from linear responses, of individual wheat entries to environment mean yield were calculated according to the various statistical procedures previously outlined. The results suggested that the linear response to environment mean yield was similar for all wheat entries. However, further inspection of the data revealed that the responses of eight entries to environment mean yield departed significantly from linearity. Although several analyses satisfactorily identified these aberrant entries, classifying them as ‘unstable’, it was concluded that the degree of departure from linearity of response was not an adequate measure of instability. Furthermore, as previously suggested by Knight (1970), it was confirmed that the relative ranking of an entry for yield stability according to such a concept varied according to the average response of the group of entries with which it was being compared.The general effects of applied nitrogen on yield components were to increase the number of ears and the number of grains per ear, and to decrease grain weight. However, only the first of these effects occurred consistently for all entries. The number and weight of individual grains per ear varied with the nitrogen treatment, often unpredictably, in a complex pattern which differed significantly between entries.

Process of grain production of rice plant in Chugoku district was analized using the same data as shown in the preceding report. The results obtained were as follows: Close relation was observed between the ripening of grains (the yield per 1, 000 spikelet) and the number of spikelets per unit area, but it differed by locality, namely, the relation was negative in Okayama but positive in Tottori, and in Hiroshima the relation was positive when the number of spikelets per tsubo was less than 75 thousand and negative when much more than it, and in other localities clear relation was not seen. The yield per 1000 spikelet had close relation with the 1, 000 grain weight, and the 1, 000 grain weight had been influenced by air temperature in ripening stage, and these relations were marked in late varieties and also at San-in district. In general, sequential correlations were found to exist among the following factors which contribute toward the yield of rice grown in Chugoku district: grain yield ∝ number of spikelets ∝ number of panicles ∝ number of tillers ∝ number of secondary tillers.

It is generally accepted as impossible to produce seed of Chinese matgrass under the natural conditions in Japan where the temperatures in autumn are too low. Studies were made in order to find out the possibility of seed production of Chinese matgrass by speeding up its flowering date at high temperature in summer (evading cool climate in autumn), through due photoperiodic treatment by making the best use of the responses of Chinese matgrass to photoperiodism. Effects of photoperiodic treatment on the heading date, stem growth, seed setting, and viability of seed obtained were examined. The test results can be summarized as follows: (1) Long-day (24hours) treatment promoted stem elongation. In case where long-day treatment was started in June, the promoting effect was greatest, but no heading was found in the case of long-day treatment plot. (2) Short-day (8 hours) treatment inhibited stem elongation. The inhibiting effect was remarkable in case where short-day treatment started in June was continued lasting for long days. The earlier the short-day treatment was started, the more in the number of stems per hill. Short-day treatment hastened the heading date, but the later in the start of short-day treatment, the less in the number of days from the start of treatment to the flowering date, and the more in the number of spikelets on the stems. (3) It was, after all, clarified that the seeds produced from the spikelets bearing flowers during the period ranging from mid-July to late August and collected in late September had germinating ability. Particularly, excellent seeds were produced from the spikelets bearing flowers during the period from late July to early August. For producing such excellent seeds, the short-day treatment started in early July is deemed most effective. (4) Seeds of excellent quality were 1.4 to 2.2mm in length, 0.3 to 0.5mm in width, 0.2 to 0.3mm in thickness, and about 120 mg in 1, 000 grain weight.

SummaryThe range, mean, genotypic and phenotypic coefficients of variation, heritability and genetic advance for various characters, of forty-seven varieties of ragi (Eleusine coracana) showed a wide range of variation and highly significant varietal differences. The genetic advance was highest for yield of straw and genotypic coefficients were higher than phenotypic coefficients for most characters. Path coefficient analysis indicated that the number of productive tillers and grain weight of main ears were the major components for seed yield.

Summary The salt tolerance of a tall, one-, two- and three-gene dwarf wheat varieties on one hand and four three-gene dwarf varieties on the other have been compared during germination and early growth: Up to 10,000 ppm salinity, dwarf Mexican wheats at all gene levels showed higher germination than the tall C 306 Indian wheat and at higher salinity levels probably the embryonic weight became more important so that Kalyan Sona (2-gene dwarf) with lesser grain weight became more susceptible than Sonalika (1-gene dwarf) which has higher grain weight. However, on the whole, there is some evidence of increased germination with the increasing number of Norin genes in saline medium. Out of the varieties tested Sonalika, Kalyan Sona and U.P. 301, with 1, 2 and 3 dwarfing genes, Sonalika seems recommendable up to a salinity level of 32 mm hos/cm. Among the four 3-gene dwarf wheat varieties (U.P. 301, U.P. 302, Hira and Lal Bahadur) U.P. 302 seems to have better salt tolerance capacity.

The maize borer, Chilo partellus (Swinhoe), is one of the major biotic constrains reducing maize productivity in Nepal. Summer maize is infested mainly by it rather than by other insect species in Nepal. National Maize Research Program (NMRP)-Rampur farm was considered as a potential spot for this study where summer maize is highly infested every year by this pest. This study was conducted during the summers of 2004 and 2005 with an objective of assessing the loss by it in maize. A maize variety, Arun-2, was used in this study. Yield loss by this pest was estimated by obtaining the yield difference between the chemically protected and unprotected maize plants. Number of plant stands, number of stem breakage, number of ears harvested, number of poor cobs, 1000 grain weight, and stem tunneling were also recorded as the yield affecting factors. The yield difference was significantly less (by 28%) in unprotected maize as compared to protected maize. Number of plant stands, number of ears harvested and 1000 grain weight were found less (by 8.5, 14, and 6%, respectively) whereas number of stem breakage, number of poor cobs, length of tunnels per plant and per tunnel length were found higher (by 16, 6, 30, and 24%, respectively) in unprotected maize. This study has suggested that application of plant protection measures against C. patellus can significantly increase maize productivity and hence can greatly contribute in poverty alleviation in Nepal. Key words: maize borer; Chilo partellus ; yield loss assessment; maize DOI: 10.3126/njst.v11i0.4085 Nepal Journal of Science and Technology 11 (2010) 25-30 Normal 0 false false false MicrosoftInternetExplorer4 The maize borer, Chilo partellus (Swinhoe), is one of the major biotic constrains reducing maize productivity in Nepal. Summer maize is infested mainly by it rather than by other insect species in Nepal. National Maize Research Program (NMRP)-Rampur farm was considered as a potential spot for this study where summer maize is highly infested every year by this pest. This study was conducted during the summers of 2004 and 2005 with an objective of assessing the loss by it in maize. A maize variety, Arun-2, was used in this study. Yield loss by this pest was estimated by obtaining the yield difference between the chemically protected and unprotected maize plants. Number of plant stands, number of stem breakage, number of ears harvested, number of poor cobs, 1000 grain weight, and stem tunneling were also recorded as the yield affecting factors. The yield difference was significantly less (by 28%) in unprotected maize as compared to protected maize. Number of plant stands, number of ears harvested and 1000 grain weight were found less (by 8.5, 14, and 6%, respectively) whereas number of stem breakage, number of poor cobs, length of tunnels per plant and per tunnel length were found higher (by 16, 6, 30, and 24%, respectively) in unprotected maize. This study has suggested that application of plant protection measures against C. patellus can significantly increase maize productivity and hence can greatly contribute in poverty alleviation in Nepal. Key words: maize borer, Chilo partellus , yield loss assessment, maize

SUMMARYThe systemic fungicide benomyl was used as a seed dressing and as a spray at two concentrations, 250 and 500 ppm, on the winter barley variety Pella. An additional treatment was a spray application of CCC at 500 ppm. All spray treatments were applied at growth stage 3–4. Without fungicide treatment, total yield in the inoculated plots was approximately 40% of that in the uninoculated plots. The 500 ppm fungicide-spray treatment significantly decreased incidence and severity scores of eyespot, the seed dressing being significant only for the latter. The seed dressing and 500 ppm spray treatments significantly increased mean yield/head, fertile tiller number and 1000 grain weight. All the fungicide treatments significantly increased total yield in the inoculated plots. There were no significant effects of CCC upon disease or upon yield, neither was there any interaction between benomyl and CCC.

The relationships between the growth habit of so-called summer vers. autumn soy beans (reported by T.Nagata in 1948) and other characteristics, which were investigated parallel, found as follows ; (1) The interrelation between the growth habit of summer vers. autumn soybeans and the earliness of flowering of the tested varieties was so closer that correlation coefficient showed as in r=0.85. Therefore, the summer type found as the earier, the autumn types the later, the intermediate types the medium late varieties. (2) 4 types were observed in the changes of flowering days (from germination to flowering) according to the differrent periods of seeding. These types were called as "the Ecological types of flowering". (fig 1) The autumn types belonged to the type I and type III, namely their flowering days were remarkably shortened when they were sown in both July and August. The type II and type IV, namely those not remarkably shortened even when they were sown in July and thereafter, were recognized mostly in the summer types. In the intermediate types, there were found all these 4 types existed. (3) It was found that the first flower was born at the heigher nodes in the autumn types and at the lower in summer typer. And the correlation coefficient calculated between these characteristics was r=+0.86. The changes in order according to the different seeding times was found as same as in that of flowering days. (4) The closer relationships between the growth habit of summer vers. autumn types and the stem length, number of blanches, grain weight per plant, and the weight of a plant were observed. Therefore, the autumn types produced comparatively more yields than the summer types. The pseudo summer types (SIp) was long as in stem length, but it had a small number of branches. (5) There was found no closer relationships between the growth habit of summer vers. autumn soy beans and the morphological characteristics, namely the forms and colour in various parts of the plant. Therefore, differences. in summer vers. autumn types were defined purely as physiological and ecological.

The effects of all combinations of nitrogen, phosphorus and potassium, with two different sowing dates, were studied using two varieties of winter wheat grown in pots. As well as studying the direct effects of these treatments on mean grain weight (1000 K weight) and grain yield, particular attention was paid to investigating any possible after-effects of these treatments in the first and second generations of the treated plants.

SUMMARY Spring wheat, var. ‘Phoebus’, drilled at 11/2 times the usual rate and grown with three rates of nitrogen was treated with 2.5 or 5 lb. CCC per acre at the sixth-leaf stage. At maturity, the height of treated plants was only 60% of that of untreated plants, but the percentage shortening was less as nitrogen increased. Although untreated plants did not lodge, CCC increased mean grain yield by 5% by increasing the number of ears and number of grains per ear. Grain weight per ear and thousand-grain weight were decreased by CCC. The explanation of the increase in shoot number by CCC is not known, but possibly less light was intercepted by the shorter plants, so that later-formed shoots survived to produce ears. CCC decreased assimilatory area by shortening stems and hence leaf sheath area; lamina area was little affected. It delayed ear emergence by up to 8 days, Leaf-area index was decreased by CCC and as it increased, net assimilation rate decreased. CCC did not affect nitrogen uptake per unit area of land but it increased nitrogen as percentage of dry matter because it decreased dry-matter yields.

Tests were conducted from 1956 to 1961 with barley and oats to study the relationship among tillers, grains per head, and grain weight, and their influence on yield under Ontario conditions. It was found that grains per head, rather than tillers per plant, was the most reliable component to use in estimating yield. However, both tillering rate and grains per head were variable and were found to be influenced by variety, seeding rate, seeding date, and soil fertility levels. Grain weight was less influenced by these factors and contributed little to the yield variation. Tillers per plant were negatively correlated with grains per head.It is suggested that in Ontario when selecting for yield, in addition to components of yield, the morphological plant characteristics determining photo-synthetic efficiency per unit area could also be considered.

An experiment was carried out to study the grain growth pattern of wheat (Triticum aestivum L.) cultivars and to find out association and linear regression of spike weight and grain weight with time. Spike characters indicated that cultivar differences were significant in all the cases with a few exceptions. Linear regression and correlation coefficients revealed that the association between both spike weight and grain weight with time were highly positively significant among the cultivars but their regression coefficients were non- significant. Key Words: Grain growth, correlation, regression, wheat. DOI: 10.3329/bjar.v34i3.3960 Bangladesh J. Agril. Res. 34(3) : 351-359, September 2009

Evaluations of dry panicle weight and threshing percentage in relation to threshed grain weights were made from grain sorghum yield trials conducted at four Iowa locations over a 3-year period. Correlation coefficients of 0.91 to 1.00 for the association of panicle weight with threshed grain weight indicated that weights from unthreshed panicles may serve as an expedient and effective selection criterion for relative grain yield among a group of hybrids.

Present investigations cover the correlation between four characters of maternal plants of rye and the corresponding characters in their offspring. Tabulated results pertain to four two-year periods for the Exp. Sta. Choryń and two such periods for the Exp. Sta. Laski, involving several plant material groups derived from various crosses with Dańkowskie Selekcyjne rye.The effects of average grain weight per ear of the maternal plant on the corresponding yields in the offspring have proved rather small, but sporadically approaching or attaining the limits of significance. The influence of resistance to lodging of the maternal plant on that same character in the offspring has proved no greater, but, in spite of the considerable multidirectional differentiation of the coefficients of correlation and regression, in 4 groups out of a total of 27 they surpassed the limits of significance, sometimes attaining high values.In contrast to these two characters, but in agreement with expectations, there was a fairly pronounced effect of 1000 grain weight and of the maternal plant height on the same characters in the offspring. Significant coefficients of regression for the former characters ranged from 0.11 to 0.22 g, and for the latter from 0.03 to 0.37 cm.The present paper also includes less numerous results of analogous investigations on the relation of characters determined in the microtrials with those examined in the next generation. These results indicate good transmission of earliness, measured by the date of earing, and of the weight of 1000 grains, but a much weaker transmission of resistance to lodging and of grain yields.The conclusions drawn on breeding strategy suggest opportunities for efficient selection under the method of recombination towards short straw and a high 1000 grain weight within maternal plants, and also the advisability of shifting the main impact of selection for yield and resistance to lodging onto the following generations.

An experiment was done at farmer's field in Sherpur district to evaluate the comparative performance of two hybrid rice varieties, Sonarbangla-2 and Sonarbangla-3 with three conventional modern commercial varieties BRRIdhan32, BRRIdhan33 and BR11 in Transplanted aman season of 2003. It is revealed that the hybrids and conventional rice varieties differed significantly among themselves with respect to different parameters under study. The highest grain yield (6.20t/ha) was recorded from the hybrid Sonarbangla-3 followed BRRIdhan-32 (5.70 t/ha) and the lowest in BRRIdhan-33 (4.17t/ha) and these differences were statistically significant. However, BRRIdhan-32 obtained significantly higher yield compared to the hybrid Sonarbangla-2. Further, it produced the maximum amount of straw (8.6 t/ha), which varied significantly with all others. Minimum days to 1st flowering (92) and maturity (108) were noticed in Sonarbangla-2 followed by Sonarbangla-3 (95 and 115), respectively. Both the hybrid had heavier grain weight (28.33-31.00g) than those of the conventional varieties (22-25g). It is noted that the hybrids maintained distinct statistical edge over the conventional varieties with regard to most of the parameters. Thus, the hybrid Sonarbangla-3 was found superior to conventional varieties for transplanting in the aman season in Bangladesh. Key words: Sonarbangla-2, Sonarbangla-3, conventional varieties, cropping pattern. DOI = 10.3329/jard.v5i1.1451 J Agric Rural Dev 5(1&2), 13-16, June 2007

1. In general the juvenile growth of interspecificTriticumand intergenericTritioum-Aegilopsamphidiploids, was normal and did not deviate from the parental behaviour. However, in the case of the interspecific hexaploids derived fromT. monococcumandT. aegilopoidesthere was an early check in growth, and all the amphidiploids derived fromA. caudatadeveloped more or less severe chlorosis.2. Most amphidiploids were intermediate between their parents in mature plant characters. However, in the hexaploidTriticuminterspecific amphidiploids there was a transgressive increase in plant height, and whilst the derivatives ofTriticum x Aegilopscrosses fell within the range of their parents, they were closer to one or other parent depending upon theAegilopsspecies involved.3. The ear morphology of theTriticuminterspecific amphidiploid was generally a composite of that of the parents, the influence of each parent being detectable. In theTriticum-Aegilopsamphidiploids, however, ear morphology was so strongly influenced by theAegilopsspecies, that there was frequently no obvious difference between the ears of amphidiploids with a commonAegilopsparent but different wheat parents.4. The fertility of the amphidiploids was low and there was no significant correlation between the fertility of amphidiploids and parents. There was a significant correlation between both the grain weight, and number of spikelets per ear, in parents and amphidiploids, but whilst the mean grain weight was about that of the parent with the heavier grain, the mean of spikelets per ear was about that of the parent with the fewer spikelets.

1. The author calculated the main yielding factor of soy bean at all prefectural agricultural experiment stations Japan, the total sum of variety investigated by him amounts to 4500. But he argues here onlyon the main yielding factor. 2. The stem length is min. 20, max. 140, mean 65, σ 21 cm. 3. The per tan yield is min. 0.0, max. 3.0, mean 1.17, σ 0.556 koku. 4. The author made the calorie calculation to compare yielding efficiencies of soy bean and paddy rice and sweet potato each other, and the results are as follows: soy bean 680000±310000 Cal., paddy rice 1570000±320000 Cal. and sweet potato 2920000±10400O Cal. 5. But the soy bean must be considered as protein resource, and the comparison of per tan protein yields are as follows : soy bean 57±27 kg. paddy rice 47±10 kg. and sweet potato 26±9kg. 6. The author also argued about the test weight and a hundred grain weight of soy bean.

Three leading varietis, Shinriki, Asahi and Norin No.18 which appeared in 1877, 1908, 1941, succesively, were reared under same cultural conditions at the Experimental Farm of the Kyushu Unversity in 1948.Comparison were made about such characters as culm length, ear lengh, number of ears per plant, total plant weight, total ear weight per plant and 1000 unhulled grain weight from the biometrical view point(table 1 and 2)and discussion was intended to forcuss the direction of imrovement of those characters above mentioned for the rice variety in the warm zone in westsouthen part of Japan.

Several methods of measuring resistance of corn kernels to Sitophilus zeamais Motschulsky were evaluated for their efficiency and adaptability. Among the 6 methods studied (grain weight loss, total progeny, percent of damaged kernels, percent of parent mortality, percent of progeny mortality, and weight per weevil), total progeny rated comparable to or better than any of the other methods for each criterion used for evaluation. Progeny mortality data are of questionable usefulness when weevil populations exceed 3 or 4 weevils per gram of grain. Grain weight loss, the best economic indicator, rated well for all criteria as a good resistance measurement, except that genetic differences among genotypes were difficult to detect for this method.

The article presents the results of the comparative assessment of varieties of spring soft wheat selection of the Federal Research Center of Agrobiotechnologies named after A.K. Chaiki in the Far East during 2015-2018, according to the main economic valuable features: technological, biochemical and baking qualities of grain. Regionalized and promising varieties having obtained with the use of spring and winter kinds of soft wheat are taken as the object of the study. High technological (thousand grain weight, virtuousness of grain total, flour extraction, sedimentation) and biological grain qualities (protein and gluten) are marked in verities Primorskaya 191 (RL 6046 x Primorskaya 63 x Primorskaya14)) and Primorskaya 206 (Nemchinovskaya 57 x Primorskaya 39). The best physical characteristics (dough elasticity, dough elasticity vs dough stretching, might of flour ) and baking qualities of grain (porocity, volume of bread and total baking assessment) are marked in varieties such as Nikolskaya (Latona x Eritrosperum 51/5) and Primorskaya 206. The variety of spring soft wheat was revealed according to the elements of productivity (length of an ear of wheat, productive bushy kinds, the number of grain, in one ear of wheat) and the best crop capacity. In 2018 a new variety was given to the «State Testing and protection commission of selective achievements of Russian Federation the Far Eastern area.

To determine the method for discriminating the stage of yield forecast, the author examined what character of rice may be utilized as an index of the discrimination. The obtained results are as follows. 1) Close relation between the rate of moisture content of ear and grain weight on the ripening stage was found, irrespective of places, years and varieties. Therefore, the ripening process of ear can be discriminated by the former. 2) Furthermore, close relation was found between the rate of moisture content of ear and percentage of milky grains. Therefore, the former can be discriminated by the latter. It was found high correlation between grain yield and fresh weight of ear at the stage when percentage of milky grains bigins to decrease. Frome these results, the stage when percentage of milky grains became 10±3%, seems to be a suitable stag for forecasting yield.

In order to know whether application of red colored hill soil to rice fields has good effects not only in the case of ordinary transplanting but in the case of early transplanting culture, and moreover to find the optimum quantity of nitrogenous fertilizers in the latter case, some experiments were carried out by the authors, the results obtained being as follows: [I] Effects of red colored hill soil put in, (a) A larger number of ears was obtained. (b) Good harvests were obtained. (c) The elongation of lower internodes were controlled. (d) Total nitrogen content in the plant decreased. (e) In consequence of the results (c) and (d), the plant became lodging resistant. The tendency above rnentioned was distinctly noticed especially in early transplanting. [II] Effects on early transplanted rice crop, (a) Decrease in a thousand grain weight of rice often liable to application of abundant nitrogenous fertilizers was checked by hill soil duplication. (b) A larger number of ears was obtained. [III] Effects on three kinds of ill-drained paddy fields which consist of mack, sandy soil and heavy clay, respectively, showed a similar tendency as above mentioned in all cases. From those facts there were elucidated good effects of red colored hill soil put in early transplanted rice fields under ill-drained condition. Crop damages frequently caused by heavy fertilizing may be thus controlled to some extent.

Design II progenies from an exotic population of corn (Zea mays L.) were evaluated in a randomized incomplete block design with two replications at two plant-population densities (17,222 plants/ha and 68,888 plants/ha) in 1970 and 1971, at Lincoln, Nebraska. Five traits were studied, i.e., grain weight, number of ears, days to flower, plant height, and ear height.It was suggested that a trait such as grain weight should be expressed on a unit area basis in the following situations: 1. when genetic parameters (except for correlation and the ratio between two values) obtained from experiments with different plant-population densities are to be compared, and 2. when combined analyses of variance of data from experiments involving different plant-population densities are to be performed to test the significance of genotype by density effects. The estimates of genetic parameters were used to compute the expected direct and indirect genetic changes in grain weight and other traits from selection for grain weight. Three selection schemes were compared, i.e. mass selection (M.S.), full-sib (F.S.) selection, and half-sib (H.S.) selection in which S1 seeds from the selected male parents are used for recombination. A ten year selection program was considered. F.S. selection appears to be the most promising of the three, if there are no practical limitations and if costs are disregarded. A high-density selection environment appears to be a little better than a low density one for family selection. Mass selection at low density may result in good gains when measured at higher densities.From a long term point of view, it is possible that selection at low densities could allow response to continue for a longer period of time and perhaps reach a higher selection limit than selection at higher densities. Long term selection studies are necessary to compare response to high and low density-selection.

A two-rowed winter barley cultivar, Carstens, was crossed with 22 6-rowed barley cultivars and one 2-rowed cultivar. The parents and hybrids, which were 2-rowed, were grown at two locations in two seasons. An F2 generation of each cross was included in the second season. The hybrids and parents were compared for winter survival, heading date, height, number spike bearing tillers, rachis nodes per spike, 1000-kernel weight, and grain weight. The hybrid significantly exceeded the higher parent in most crosses for height, number rachis nodes per spike, and in every cross for 1000-kernel weight. Significant midparent heterosis was observed in most crosses for winter survival. Heterosis for grain weight was obtained in the 2-rowed × 2-rowed cross. The 2-rowed parents were distinctly less hardy than the 6-rowed parents and expression of characters like number of tillers and grain weight was confounded with winter survival. In hybrids from 6-rowed × 2-rowed crosses the increased number of rachis nodes per spike and heavier kernels contribute to higher grain yields, but these influences are offset by the restricted row number and fewer kernels per spike.

Common milkweed (Asclepias syriaca L.) is a deep-rooted perennial weed that has increased in occurrence in recent years and has caused much concern among landowners. Because it occurs frequently in dryland sorghum [Sorghum bicolor (L.) Moench], a 3-year competition study using paired plots was conducted to determine the degree of yield loss caused by common milkweed. Sorghum yield and number of heads per hectare were significantly reduced by common milkweed competition each of the 3 years. Common milkweed reduced average yield by 21% and number of sorghum heads per hectare by 14%. Even low populations (less than 12,000 plants/ha) of common milkweed resulted in severe yield losses. Grain weight per head was significantly reduced by common milkweed competition in 1970 and 1972 but not in 1971. Competition had no effect on sorghum 500- seed weight in 1971 or 1972. Percentage protein (Kjeldahl method) of sorghum grain was significantly increased by competition in 1972 but not in 1971.

In the previous experiment, it was shown that the late transplanting resulted in the remarkable decrease of yields.. with the aim to analyze the reduction of yield caused by the late transplanting, we have compared the growth and yield of rice crop under two different treatment; one sown densely (18 × 18cm) and other sown sparsely (24.2 × 24.2cm) on the seed bed, both transplanted later than usual. The seedlings in sparsely sown plot produced their tillers regularly; they have more than thirty tillers already at the time of transplanting, and howed high yield. But in the other plot the tillering is inhibited; no one tiller at the time of transplanting, and showed low yield, about half of that in the usual cultme. After the seedling were transplanted, the tillering has continued to some extent in former plot, but the many new tillers appeared at the higher nodes of the stem in letter plot. The high yield obtained in the sparsely sown plot may be explained by the following five reasons: (1) Seedlings were grown for longer time under favourable condition because the seed bed was more fertile than the paddy field and also it was rsurrounded by shelter-hedge. (2) As rice plants had good enough space to grow until the time of transplanting (5thof July) they could produce many healthy tillers from the lower nodes of their stem; 30 or more tillers were growing at the time of transplanting. (3) consequently the larger number of tillers and ears were produced. (4) As tillers from the lower part of the stem appeared early, the date of heading was also early, resulting heavy grain weight. (5) As far as the result of this experiment was concerned, the rice crop sown sparsely seemed to be able to produce higher yield, even when it transplanted later than usual culture method. But this trend might not be always observed because the different result would be obtained under different weather. The low yield of densely sown plot may be explained by the following fact; (1) tillering was inhibited seriously because of the narrow space given, and after they were transplanted. Appeared the tillers from the upper part of the stem as well as the tillers of higher order. (2) The number of tillers and stems were fewer than those of other plots.(3) As the tillering was delayed, date of heading was also delayed, and the light grains were produced.

Two groups of samples were used as materials. One of the groups consisted of the crops of variety Norin No.1 from eight prefectures, each representing the soft-rice-producing region in Japan, and the other group consisted of the crops of the same variety from eight prefectures representing the hard-rice-producing regions. The water-content was measured by means of the KETT infra-red ray water-content meter of the Sanwa Electric Institute (calibrated with Mr.NAGAHARA's desiccation-method at 135°C), the specific gravity by means of the REISHAUER's pycnometer, and the hardness by means of the hardness meter of the Kiya type. The results obtained are as follows : (1) The water content of soft rice was about 1% higher than that of hard rice. (2) The 1000 grain weight of soft rice was about 1.7 g. higher. (3) The specific gravity of soft rice was a little (0.01) higher. (4) The fracture hardness was 1.0 kg. lower and the breaking hardness, 0.8 kg. lower. (5) The comparison of its correlation coefficients with those of hard rice showed no significance. Then, the water-content was changed between 10 % and 20 % at an interval of 2 %, and the other properties above mentioned corresponding to each level of the water-content were measured. As the results : (6) The 1000 grain weight of soft rice was invariably about 2g. heavier than that of hard rice. (7) The specific gravity of the former was invariably about 0.02 higher. (8) In the hardness of fracture and breaking, there was no difference between the two kinds of rice, either of the properties depending on water-content. (9) The correlation coefficients were found to exsist significantly only (a) between the water-content and the 1000 grain weight ; (b) between the water-content and the fracture hardness ; and (c) between the 1000 grain weight and the fracture hardness. Soft rice was more or less lower than hard rice, in (a) and there was much difference in (b) and (c) between the two sorts of rice. Nearly all the researches on rice quality in the past have left the physical properties of soft and hard rice and their differences dark. But the present research has clarified that at least the 1000 grain weight and the specific gravity of soft rice, whether in a natural state or at a level of water artificially controlled, are higher than those of hard rice. The present author believes that it can be ascribed to the quantitative difference in solid materials, that is, largely in starch, and also in protein, between soft rice and hard rice.

1.In the previous experiment, it was shown that the late transplanting of rice results in a remarkable decrease of yields, particularly when the seeds are sown densely in the nursery, and thinner seeding seems to be able to raise seedlings to produce higher yield, even when they are transplanted later than usual. 2. With the aim to analyze the low yields caused by late transplanting, wa have compared the growth and yield of rice plarnts sown at four different densities in the nursery ; i. e. 541cc, 180cc, 45cc and 18cc of seeds were sown respectively per 3.3m2. Seedlings thus obtained were transplanted under the same density ; 90 hills per 3.3m2 (24.2cm×15.2cm) of paddy field. 3. Yields of the plants transplanted 30 days later when compared with the control are as follows : (i) Plot sown at the density of 541cc per 3.3m2 gives only three quarters of the yield of the control culture. (ii) Sparsely sown plot (180cc, 54cc and 18cc plot) showed nearly the same or even larger yields than that of the control. 4. The high yields obtained in the sparsely sown plots may be explained as follows : (i) As the seedlings had good enough space to grow in the nursery, they could produce many healthy tillers on the lower nodes by the time of transplanting (July 5).(ii) Consequently the larger number of tillers and ears were obtained from lower nodes.(iii) As tillers from the lower node start early in growth, and their heading take place also early, In such a case even the tillers produced from upper nodes on late transplanting, ded not so much delay in heading (iv) The reduction in grain weight, grain numbers per ear, and fertility were compensated by the increased number of stems. 5. The low yield of the 541cc plot may be explained as follows : (i) Many of the main stems died prematurely. (ii) Tillers have appeared from the upper nodes. (iii) As tillering delayed, heading also became late, fertility, decreased and reduced weight of grains resulted. (iv) Although the number of stems or ears were equal to that of usual culture it, could not overcome the seriously decreased weight of each ears, in this case.

The results of experiments carried out from 1950 to 1958 are reported here conclusively. Lowering of rice yield caused by the delayed transplanting, especially when seeding was made very densely on seed-bed, can be explained as follows: 1) Seedlings are grown to too old, 2) shifting of tillering nodes to upwards, and 3) consequently delaying of tillering and heading takes place. Therefore if the sowing is made lately, or sparsely at the normal sowing date on the nursery-bed, and transplanted lately, the yield can be almost as much as those of the standard culture, because these lately transplanted rice plants can carry on rapid growth and heading does not delayed due to the following reasons; 1) As rice plants have good enough space to grow until the time of transplanting, they can produce many healthy tillers from the lower nodes of their stem. 2) Consequently the larger number of tillers and ears are produced. 3) As tillers from the lower part of the stem appears early, the date of heading is also early and which results in heavy grain weight. After late transplanting, the progress of accumulation and translocation of starch, sugars, total carbohydrates or nitrogen compounds in the plants sown lately or sparsely at the normal date of the plots were found practically not different with standard culture plot.

THE ear of cereals such as barley and wheat is an important photosynthetic organ in providing carbohydrate substrate for grain filling. This has been established by several workers, most recently by Archbold1 for barley and Asana and Mani2 for wheat. Their technique, as of previous workers, involved opaque shading of the ear to prevent photosynthesis, the resulting reduction in grain weight being taken to represent the normal ear contribution. Reductions of the order of 30 per cent have been obtained (Archbold measured whole ear weight only).

The author measured the weight of each rice grain divided into the two classes : the normal and the inferior, by the texture of grain, harvested from 155 experimental paddy fields distributed in Iwate Prefecture, in 1950, and made a ferquency distribution table (Table 3). Confliction came from the fact that the normal grains contain those which are lighter than the mean weight of the inferiors, and on the other hand, the inferiors contain those which are heavier than the mean weight of the normals, the frequency distributions of both being of wide ranges from 6 mg. to 24 mg. classes. The lower limit of grain weight of the upper 95% range in the normals was 16 mg. and the upper limit of the lower 95% range in the inferiors was 18 mg. About 16 mg. may be established as a limit weight between the normal and inferior rice grains.

(1) The author examined the flowering order of the sesame, dividing the flowers, by there position, in two sorts of the chief flowers and the side flowers. (2) The difference in the days of flower opening between node to node was on average about one day in the chief flowers, advancing from the bottom to the upper part almost straightly. (3) Many aborted were found in the chief flower groups at the bottom of stem, while in the side flowers they located at various positions. (4) The percentage of fruit-setting was rather low at the lower flowers, highest at the middle and suddenly decreased at higher part. (5) The side flowers were observed less than the chief flowers both in the percentages of flower-setting as well as of fruit-setting. (6) The length of pods was short at the bottom, increasing toward the middle part, but gradually lessened from the middle to the high, showing a sudden decrease at the top, while in thickness and breadth they were smaller at the low to the middle parts and then gradually decreased upwards. (7) The grains in a pod were rather few in number at the low part, largest at the middle and a few at the high part. (8) The dried grain weight was heavy at the low part, while lather light at the middle, and the lightest at the high part.

Summary In main ears of Triple Dirk wheat plants grown at a temperature of 21/16°C under natural daylight, grains in the second florets of the central spikelets maintained the highest growth rates (1· 66 mg/grain/day), those in the first florets of the basal spikelets the lowest rates. Sterilization of the basal one or two florets of the central spikelets before anthesis led to compensating increases in both grain weight and the numbers of grains set in other parts of the ear, in the two varieties examined. In one variety, Triple Dirk, under high light intensities, sterilization of the first or second florets of the central spikelets led to significant increases of up to 20%, in grain yield per ear, compensating grains being set in distal florets of the central spikelets and additional and heavier grains being formed at the top and bottom of the ear. Eighty-eight percent of the 14C assimilated by ears 15 days after anthesis was found in the grains at maturity, and was fairly uniformly distributed between spikelets. 14C assimilated by flag leaves, on the other hand, was distributed preferentially to the lower central spikelets, and to the second grains, and partial sterilization of the central spikelets greatly increased the proportion of 14C in the apical and basal spikelets. We conclude that the setting of grains in upper florets, and grain yield per ear, may be reduced by rapid development of grains from the first flowers to reach anthesis.