Total Dry Weight Production Research Articles

Growth and dry matter partition wheat plants in response to seed vigor and water restriction

Abstract: The quality of the seeds and the occurrence of stresses are decisive for the development of the crops. Thus, the work aimed to verify the effect of seed vigor on growth and dry weight partition of wheat plants subjected to water stress. For growth evaluation, the experimental design was completely randomized, in a 2 x 2 x 8 factorial scheme (vigor level x water regime x collection time), with four replications. To evaluate the yield of the seeds, the design was completely randomized, in a 2 x 2 factorial scheme (level of vigor x water regime), with four replications. Total dry weight, dry weight production rate, relative growth rate, leaf area ratio, leaf area, solar energy conversion efficiency, dry weight partition and harvest index were evaluated. Total dry weight production, dry weight production rate, leaf area, leaf weight ratio, solar energy conversion efficiency and yield were higher for plants from highly vigorous seeds under field capacity. The yield was higher for plants with high vigor compared to those with low vigor in field capacity.

PRODUCTIVITY Pueraria phaseoloides var. Javanica FERTILIZED WITH MANURE FROM CATTLE OFFERED CONCENTRATE CONTAINNING DIET SUPPLEMENTED WITH AMMONIUM SULFAT

This study aims to determine the optimal dosage of manure derived from cattle fed concentrated rations supplemented ammonium sulfate which can increase the productivity of Pueraria phaseoloidesvar .Javanica. The design used in this experiment was Completely Randomized Design (RAL) with 4 treatments and 5 replications. The four treatments were fertilized with doses of 10, 15, 20 and 25 tons / ha, respectively for the treatment of A, B, C and D, so overall there were 20 pot experiments. The study was conducted for 12 weeks. Observed variables were plant length, number of leaves, number of branches, dry weight (DW) of leaves, DW of stem DW, total BK, leaf color, leaf stem ratio (LSR) and leaf weight ratio”(LWR). The results showed that legumes treated A B, C and D produced high crop, leaf area, leaf color, LSR and LWR were not significantly different (P> 0.05). The treated legume C. resulted in a significantly higher leaf number than the treated legume A, B and D (P <0.05). The number of branches and DW leaves on legumes treated with C were significantly higher (P <0.05) than those receiving treatment A. and were not significantly different with legumes treated with B and D (P> 0.05). The DW of stem and total DW production from legume treated C were significantly higher with those treated with A and B (P <0.05) and the difference was not significant with those treated with D (P> 0.05). From the results of the study it can be concluded that legume treated with C or fertilized with manure derived from cattle fed concentrate containning diet supplemented ammonium sulfate at a dose of 20 tons / ha yield of leguminous productivity Peuraria phaseoloides var. javanica maximum.
 Keywords: manure, pueraria phaseoloides, productivity.

Forage Production and Nutrient Composition of Different Sorghum Varieties Cultivated with Indigofera in Intercropping System

The experiment aimed to evaluate the production of nutrients by different varieties of sorghum grown with high valuable indigofera legume in intercropping system and to determine the suitable variety of sorghum that produced the highest nutrient in the system. The experiment was done at Jonggol Animal Science Teaching and Research Unit (UP3J) Jonggol, from November 2014 to March 2015. This experiment was conducted using completely randomized design with 2 factors (3 x 4) and 4 replications. The first factor was sorghum varieties (PATIR 3.2 (S1), PATIR 3.7 (S2), and CTY-33 (S3)). The second factor was indigofera composition (0% indigofera (I0), 30% indigofera (I1), 40% indigofera (I2), and 50% indigofera (I3)). Data were analyzed using analysis of variance and HSD test. There was no interaction among varieties of sorghum and indigofera composition. Indigofera population of up to 50% in multiple cropping system had the highest (P<0.01) dry matter content, crude protein content, ash content, total fresh weight production, total dry weight production, total crude protein production, total ash production, and carrying capacity. Sorghum variety CTY-33 planted in multiple cropping system had the highest (P<0.01) dry matter content, total dry weight production, and (P<0.05) total crude protein production. PATIR 37 sorghum variety planted in multiple cropping system had the highest (P<0.05) ash content and (P<0.01) total ash production. It is concluded that Indigofera population of up to 50% planted with different varieties of sorghum in multiple cropping system had the highest nutrient production.

Physiological Processes Affected by Low Night Temperatures in Sweet Pepper Plants

Extreme temperatures may be frequent in the coming decades as result of climate change. However, we need to keep crop yield high by means of breeding and improving crop management. And first we need to understand the physiological processes affected. Little is known about how cold affects plants during the night (when the incidence is higher), so that was the objective of our work. The response of sweet pepper seedlings to different doses of low night temperature (LNT) (1/4/7 nights at 6/18°C) was evaluated by measuring changes in potentially sensitive physiological parameters.LNT reduced water uptake and relative water content (RWC) of plant tissues probably due to a decrease of hydraulic conductivity but not to an increase of transpiration. The reduced RWC resulted in loss of turgor, which reduced stem elongation and leaf expansion, and therefore light interception. LNT enhanced the accumulation of sucrose and starch in the leaves during the night. Starch accumulation did not affect photosynthesis due to feedback inhibition. Although photo-inhibition was observed, CO2 uptake was not affected and neither was total dry weight production after 7 cold nights. Specific leaf area decreased with LNT. However, that was not correlated with starch accumulation so it may be due to accumulation of other compounds involved in cold hardiness, such as sucrose. LNT didn’t stop the clock that regulates these plant processes, but affected them by modifying their physical properties.In conclusion, the occurrence of LNT leaded to shorter plants with thicker but smaller leaves. The decrease of cell elongation was due to the reduced water uptake capacity. Although biomass was not affected after 7 days because photosynthetic rate was kept high during the day, the reduced light interception may affect it eventually if stress doses are extended.

Variation Between Cut Chrysanthemum Cultivars in Response to Suboptimal Temperature

To breed for more energy-efficient cut chrysanthemum (Chrysanthemum morifolium Ramat.) cultivars it is important to know the variation of the temperature response existing in modern cultivars. In a greenhouse experiment with 25 chrysanthemum cultivars, a significant variation was observed in temperature response (16 °C or 20 °C) for reaction time, total dry weight produced, stem length, and flower size and number. To study this genetic variation in temperature response over a larger range of temperatures (15 °C to 24 °C), four contrasting cultivars (Annecy, Delianne, Reagan, and Supernova) were selected in a second experiment. Furthermore, a third experiment was performed in which the cultivation period was split into three phases and the influence of temperature in each of these phases was studied for the four selected cultivars. Dry weight production in all cultivars was very sensitive to temperature during the long day period. Relative growth rate showed an optimum response to temperature, with the optimum around 24 °C. Net assimilation rate also showed an optimum response to temperature, whereas leaf area ratio increased linearly with temperature. Compared with these temperature effects during the long day, the effect of temperature on absolute growth rate during the short day was, depending on the cultivar, relatively small or even absent. The reaction time, on the other hand, was very temperature sensitive, showing an optimum that was cultivar dependent. The temperature response of the total dry weight production during the whole cultivation period was, therefore, very cultivar dependent. Furthermore, depending on the cultivar, stem length increased with temperature, especially during long day, as a result of both increasing internode number and average internode length. The response of both flower size and number to temperature was also highly cultivar specific. The possibilities of using this genetic variation for breeding are discussed.

Omega-3-Fatty Acid Concentration in Portulaca oleracea is Altered by Nitrogen Source in Hydroponic Solution

Purslane (Portulaca oleracea L.) has been identified as an exceptionally rich source of α-linolenic acid (LNA), an essential fatty acid that is beneficial in reducing the incidence of coronary heart disease and certain cancers. In general, about two thirds of the LNA in terrestrial plants is associated with chloroplasts. A green-leafed unnamed cultivar of purslane and a golden-leafed cultivar `Goldberg' were grown hydroponically in a complete nutrient solution with 14.3 mm nitrogen provided as nitrate (NO3-) and ammonium (NH4+) forms to yield NO3--N: NH4+-N ratios of 1:0, 0.75:0.25, 0.5:0.5, and 0.25:0.75. Young leaves, harvested 18 days after treatment initiation, were analyzed to determine the fatty acid composition and concentrations, and thylakoid protein and chlorophyll concentrations. Although the leaves of plants grown with a NO3--N: NH4+-N ratio of 0.5:0.5 contained 239% and 114% more LNA than plants grown with ratios 1:0 and 0.75:0.25, respectively, they contained only 41% and 26% more chlorophyll. The green-leafed cultivar had higher (39%) chlorophyll concentrations than `Goldberg', but both cultivars had similar LNA concentrations [per g dry weight (DW)]. These results suggest that the LNA concentration in the fatty acid-rich species P. oleracea may not be as closely associated with chlorophyll concentration as reported earlier for other plants. Leaves of plants grown in solutions with 0.25:0.75 NO3--N: NH4+-N ratio contained 35% less LNA per g leaf DW than the leaves of plants grown in nutrient solutions with a 0.5:0.5 ratio. Although total DW production was not affected by the NO3--N: NH 4+-N ratios in the nutrient solutions, the green-leafed cultivar produced higher fresh weight, leaf area, total DW, and number of shoots than `Goldberg'.

Intra- and Inter-Specific Competition of Poa crassinervis Honda and P. annua L.

Both intra- and inter-specific competition between Poa crassinervis and P. annua were studied by planting a target plant of either species at the center of a pot and surrounding with neighbouring plants of the same or the other species at three levels of planting density. The magnitude of the competitive ability was evaluated by growth of the target plant with the reciprocal technique.The target plants of P. crassinervis had larger total dry weight in mixed stands with neighbouring plants of P. annua at a plant density of three plants per pot, compared with its total dry weight in the pure stand. However, the target plants of P. annua did not show any difference in dry weight between the two stand types at any plant density. When reciprocals of the target plant dry weight were plotted against neighbouring plant densities, the pure stand regression line of P. crassinervis located a little above its mixed stand line, and the interspecific competition with P. annua appeared to be greater than the intraspecific. In P. annua, the two regression lines were mostly overlapping at all plant densities of the neighbouring plants.The results of both total dry weight production of the target plants and the reciprocal analysis suggested that the magnitude of interspecif is competition between these two Poa species of the genus was very small. The magnitude of their interspecific competition appeared to allow the two species to live sympatrically in western Japan.

Seed germination, nitrogen nutrition and water requirements of the edible herbCorchorus tridens (Tlliaceae)

The use of Corchorus tridens for food and medicine is popular among rural communities in the Eastern Transvaal lowveld of South Africa. Its prolific seed production, spontaneous germination, and distribution in water stressed regions suggest that cultivation of this species could be feasible. A study was initiated to investigate this. Seed coat scarification improved the percentage of germination by almost 30%. A high temperature range (15–30°C) increased germination relative to a low temperature range (10–20°C). A factorial experiment consisting of three nitrogen forms (ammonium sulphate, potassium nitrate and a 1:1 mixture of these) and three levels of irrigation (at 35%, 50% and 75% field capacity) was conducted. Productivity improved mostly with nitrate fertiliser, followed by a nitrate-ammonium mixture and lastly with ammonium applications. The nitrogen form and water treatment did not significantly increase total dry weight production, mean relative growth rates or root:shoot ratios.

Variation in Salt Tolerance and Ion Accumulation among Subterranean Clover Cultivars

Increased productivity of forage crops under saline conditions is a desired characteristic in irrigated areas in both the USA and Australia. Clover (Trifolium) species are often used in single or mixed stands. Studies were conducted to determine physiological mechanisms and the extent of variability for salt tolerance among cultivars of subterranean clover. Six cultivars of subterranean clover (T. subterraneum L.) belonging to three different subspecies, brachycalycinum (cv. Clare and Wenijup), subterraneum (cv. Bacchus Marsh and Tallarook), and yanninicum (cv. Meteora and Trikkala), were tested for salt tolerance during germination and emergence and at the vegetative stage of growth in sand cultures salinized with 20 to 80 mM NaCl. Cultivars differed in final emergence, growth rates, salt tolerance, and ion accumulation. When salinity was applied at the time of seeding, the cultivars Clare and Tallarook were the most tolerant. When plants were salinized after the three‐ to four‐trifoliate leaf stage, Clare had the highest relative salt tolerance as defined by shoot dry weight yield reduction as a percent of the unsalinized controls. Relative salt tolerance followed the order Clare &gt; Bacchus Marsh = Trikkala = Tallarook &gt; Meteora = Wenijup. Meteora had the highest productivity as defined by total dry weight production under high NaCl treatment. Productivity of clover under saline conditions requires high growth potential and low reduction in yield with increasing salinity. High productivity under salinity stress was positively correlated with restricted Na+ uptake in the shoot and the maintenance of high K+/Na+ ratios.

Growth and Development of the Main Greek Oriental Tobacco Cultivars

Abstract Growth and development of seven Oriental tobacco cultivars, representing aromatic, neutral and taste type tobacco grown in Greece, were studied at Drama, Greece, during 1982 and 1983. The growing period from transplanting to flowering ranged from 65 to 80 days and was the same for both years. plant height increase followed a sigmoid curve, the number of harvestable leaves developed almost linearly with time, and total dry weight production and leaf area increase can be described by a logarithmic curve. The effect of year on all parameters was significant, but cultivar differences were consistent. Assimilation rates during the whole period ranged from 0.1 g to 3.0 g per day per plant in 1982, and from 0.1 g to 2.7 g in 1983. Dry weight distribution in the plant parts and final yield production for the cultivars tested were also recorded.

A COMPARISON OF THE RESPONSES OF LOLIUM PERENNE L. *, HOLCUS LANATUS L. AND DESCHAMPSIA FLEXUOSA (L.) TRIN. TO A LOCALIZED SUPPLY OF NITROGEN

SUMMARYThree grasses were grown in a split‐root solution culture experiment in which only a fraction of the root system of each plant was supplied with 4.0 mol m−3 N as NH4NO3. The solutions were labelled with 15NO3 or 15rNH4 during the final 24 h of the experiment. Deschampsia flexuosa, unlike Holcus lanatus and Lolium perenne, showed no reduction in total dry weight production relative to the controls. Proportionately greater increases in specific N‐absorption rate were measured in D. flexuosa compared with H. lanatus and L. perenne. All three species exhibited large changes in root morphology (length : dry weight). In D. flexuosa such changes were confined only to those roots having direct access to N (+ N roots); in H. lanatus and L. perenne this response occurred also in the rest of the root system (‐N roots). The proportion of 15N transported to the ‐ N roots was greater in H. lanatus and L. perenne. Increased transport of ammonium‐N to the shoot was found in D. flexuosa and, it is suggested, this stabilized the root: shoot ratio and maintained maximum relative growth rate. The smaller absolute N demand of D. flexuosa was such that responses to maximize N uptake, to confine to a greater extent the utilization of N to +N roots, and to maintain N supply to the shoot, ensured full compensation for the restricted N supply. The inherently higher N demands of H. lanatus and L. perenne could not be met by increases in specific absorption rates. In addition, the transport of relatively greater amounts of 15N to – N roots rather than to the shoot, and the consequent increase in root: shoot ratios prevented compensation from being achieved to the same extent.Thus, the efficient utilization of dry matter and nutrient resources appear to be important factors enabling D. flexuosa to grow effectively under restricted conditions of nutrient supply.

Crested Wheatgrass Vigor as Affected by Black Grass Bug and Cattle Grazing

Crested Wheatgrass Vigor as Affected by Black Grass Bug and Cattle Grazing

Development of yield in two grain-sorghum hybrids. I. Dry weight and carbon-14 studies

Growth and development of two grain-sorghum hybrids (De Kalb E57 and Texas 610) were examined under glasshouse conditions by sequential harvesting and the use of I4C. The grain yield per plant of Texas 610 was higher than that of E57, with higher total biological yield and similar harvest indices. The contribution to grain weight at maturity, of carbon assimilated prior to anthesis, was about 10% for each hybrid. The leaves were the main source of this material. After anthesis, dry weight data indicated that temporary storage of assimilates before retranslocation to the grain was of greater importance in Texas 610 than E57. This storage was largely in the leaves (including sheaths), upper internodes, and roots. A high grain-growth rate was maintained for longer by Texas 610 than by E57. Total dry weight production after anthesis in both hybrids was, at all stages examined, more than sufficient to maintain grain growth.

Effects of Partial Defoliation on the Growth of Liriodendron tulipifera L. Seedlings

Partial defoliation of Liriodendron tulipifera L. by removal of leaflets as they emerged from the protective buds affected a variety of growth parameters. Reductions occurred in total dry weight production, the percentage of new growth devoted to foliage, leaf area ratio, and the increment of leaf area per unit of leaf weight increment. Increases occurred in unit leaf rate and the rate of production of new leaves. Weight of leaves near the base of the seedlings was unaffected by treatment but leaves developing at the end of the growing season were larger on defoliated plants. The net effect of removing one-third and two-thirds of the developing leaflets was to reduce total dry weight production by 14 and 42 per cent respectively.

Yield and Sugar Production by Sugar Beets as Affected by Leaf Area Variations Induced by Stand Density and Nitrogen Fertilization1

AbstractSugar beets (Beta vulgaris L.) were grown in combinations of three stand densities with four rates of N application during the season and the leaf area and production of dry weight and sugar measured at weekly intervals to determine the effects of superoptimal N fertilization on beet growth and quality at Huntley, Montana. The highest sugar percentage and yield of extractable sugar were produced without N fertilization with beets 46 cm apart in the row. The highest extractable sugar yields were associated with the lowest leaf area index both at harvest and throughout the season, with the lowest leaf area duration, and with the lowest top:root ratios on a dry‐weight basis. Net assimilation rates per unit of leaf area were negatively correlated with leaf area index and leaf area duration. Optimum leaf area index did not appear to be much above 1.9 at October harvest or above 3 at any time during the season. Although the best beets were produced without N fertilization on this fertile soil, lower rates of N than those used might have been beneficial. High N rates produced more leaf area and higher total use of sunlight, as measured by total dry weight production, but resulted in lower sugar yields and juice purity. The net photosynthesis was calculated to be only about one‐third of the theoretical total photosynthesis for the climatic conditions.

Physiological and ecological studies on the oestrogenic isoflavones in subterranean clover (T. subterraneum L.). II. Effects of phosphate supply

Two experiments with the Mt. Barker strain of subterranean clover and one with the Dwalganup strain were conducted. In each experiment, increase in phosphate supply led to increases in total dry weight production. As phosphate deficiency became more acute in the Dwalganup strain, the leaf concentrations of two isoflavones, formononetin and genistein, increased as much as twofold; a third isoflavone, biochanin A, showed little change. In the Mt. Barker strain the concentrations of genistein and biochanin A increased about twofold with increasing severity of phosphate deficiency, while those of formononetin increased at least fourfold. It is suggested that isoflavone formation in clover leaves increases under phosphate deficiency, and that this is associated with increased carbon substrates in the leaf cells. The relations between isoflavone levels and oestrogenic potency are discussed. Phosphate deficiency may be indirectly related to oestrogenic potency through its influence on isoflavone levels.