Tillering Phases Research Articles

Impacts of chilling at the tillering phases on rice growth and grain yield in Northeast China

AbstractChilling is a major constraint on rice production in mountainous regions of the tropics and in the temperate rice‐growing zones of the world. In this study, our goal is to quantify the impacts of chilling at the tillering phases on rice growth and grain yield. In 2017 and 2018, we conducted a factorial chilling treatment at four temperatures (T1, T2, T3 and T4) and four duration days (D2, D4, D6 and D8) on rice plants at the early, middle and late tillering phases. The results showed that chilling at the tillering phases delayed rice growth period. The rice grain yield slightly increased with decrease in chilling temperature but significantly decreased with increase in chilling duration at the tillering phases. For the chilling treatment at T1 (lowest temperature), the D2 (shortest duration) had positive effects on rice yield, while the D8 (longest duration) had adverse effects on rice yield. The middle and late tillering phases were the critical growth phases for rice spike numbers formation, with the increase in temperature and duration, the rice spike numbers per plant significantly decreased. The decrease in chilling temperature and increase in chilling duration both decreased rice thousand‐grain weight under chilling treatments at tillering phases. The prolongation of days from emergence to flowering led to increase in rice aboveground biomass per plant and allocation index of stem; however, the decrease in days from flowering to maturity led to reduction in allocation index of panicle and grain yield under chilling treatments at tillering phases. This study could help farmers to better understand the impacts of chilling on rice growth and yield, especially for rice that are prone to chilling.

Effect of ultrafine metal particles and their oxides on antioxidant enzyme activity, spike productivity and grain quality of spring soft wheat

The results of field experiments in the scope of studying the effect of various options of ultrafine metal particles, their combinations, oxides on the content of antioxidant enzymes (catalase, malondialdehyde) as well as carotenoids in the tillering phases, stem elongation and spring wheat ear stage are presented. The influence of the above options on the formation of spike productivity (number of grains and grain weight per spike) and grain quality indicators (hardness, unit, gluten amount) are considered.

ВЛИЯНИЕ СРОКОВ ВНЕСЕНИЯ БИО- И ГУМИНОВЫХ ПРЕПАРАТОВ НА ПРОДУКТИВНОСТЬ ЯРОВОГО МНОГОРЯДНОГО ЯЧМЕНЯ

This article presents the results of research of the influence of bio-and humic preparations on the productivity of spring multi-row barley. It was concluded that they have an effective influence on plants. Studies have shown that when processing crops with potassium HUMATE in the tillering phase and entering the tube, the largest numbers of barley plants were preserved for harvesting and a higher productive bushiness compared to the control was observed. The third use of the preparation slightly reduced studied indicators. It was also established that, on average, for 3 years of research, the use of potassium HUMATE in the tillering phases, entering the tube and earning contributed to a significant increase in the number of grains in the ear and the mass of 1000 seeds. The research results indicate that the yield of spring multi-row barley of Vakula variety significantly changed according to experiment varieties. The maximum increase was provided by three-time treatment of crops with potassium HUMATE. After conducting a correlation and regression analysis, it can be concluded that the yield of spring barley was equally dependent on the elements of productivity. There was a close positive relationship. Consequently, the productivity of spring multirow barley plants is significantly influenced by bio-and humic preparations.

Formation of Nonspecifi c Resistance in Winter Wheat Plants by the Hydrogen Peroxide Treatment

Aim. The aim of the investigation was to study the effect of hydrogen peroxide on the activity of antioxidant enzymes, pigments’ content and productivity of winter wheat in order to determine the biochemical mechanisms of induced winter wheat plant resistance during ontogenesis in the fi eld. Methods. The study of physiological and biochemical parameters were carried out on winter wheat varieties of the wooded steppe (Poliska 90) and steppe (Skala) ecotypes at the tillering and fl owering phases. The experimental plants were foliar treated with hydrogen peroxide (Н 2 О 2 ) in concentration of 1∙10 –1 M twice, with a 3-day-interval, while the control ones – with distilled water. Spraying of plants was performed at spring (tillering phase). Lipid peroxidation (LPO) was determined as the formation of a peroxidation end product — malondialdehyde, which content was determined as the extinction of its condensation product with thiobarbituric acid. The activity of superoxide dismutase (SOD) was determined by a method based on the ability of SOD to inhibit nitroblue tetrazolium recovery by superoxide radicals in the light in the presence of ribofl avin and methionine. The activity of catalase was calculated using the extinction coeffi cient of − 39.4 mM –1 cm –1 . Results. It was established that after 24 h of hydrogen peroxide treatment the processes of lipid peroxidation were intensifi ed and antioxidant enzymes’ activity was decreased in two varieties. In the next phase of ontogenesis (fl owering) antioxidant enzymes’ activity increased in both varieties: Poliska 90 and Skala, which suppressed the LPO growth. Conclusion. Treatment of plants with hydrogen peroxide promoted the formation of non-specifi c plant resistance and increased grain productivity of winter wheat varieties investigated.

Photosynthetic efficiency and survival of Dactylis glomerata and Lolium perenne following low temperature stress

Resistance to low temperature is crucial for overwintering crops. In this work we compared the resistance to low temperature treatment of some varieties of two forage grass species Dactylis glomerata L. and Lolium perenne L. in order to elucidate the reason for the better resistance found in some species. The variety Amila of D. glomerata and Diament of L. perenne were more tolerant to low temperature stress during the emergence and tillering phases as compared to the varieties Amera and Gagat. The improved tolerance and ability for recovery after stress were associated with the better recovery of photosynthetic efficiency of these varieties and better survival of their shoots after low temperature stress.

Wheat seedlings growth response to water deficiency and how it correlates with adult plant tolerance to drought

SUMMARYImproving resistance to water and osmotic stresses at the seedling stage is becoming a much more important target for wheat breeders due to an increase in the frequency and severity of drought occurrences at the crop establishment and tillering phases in many wheat growing areas of the world. Ninety-six diverse wheat genotypes were laboratory tested for germination and growth response under osmotic stress induced by polyethylene glycol (PEG). Germination percentage, mean germination time, coleoptile length, shoot length and shoot growth rate were compared under stress (−0·4 MPa) and control (0·0 MPa) conditions. The same genotypes were previously grown in field trials exposed to drought stress during the anthesis and/or grain filling growth stage along with control (optimum) conditions. Grain yield (GY) and 19 other traits of agronomic importance (earliness, stem-related traits, number of kernels, mass of 1000 grains, etc.) were recorded. All seedling traits under PEG-induced water stress showed the highest relationship with the stem and stem-related traits of adult plants. To study the correlation between stress tolerance in the seedling and reproductive stages, three stress indices (tolerance index (TOL), stress susceptibility index (SSI) and stress tolerance index (STI)) for the seedling traits and GY under pre- and post-anthesis drought stress were calculated, based on a mean trait value obtained under stress and the corresponding trait value under control conditions. The ranking of the genotypes based on TOL and STI from seedling traits was found in most cases to be significantly correlated with the ranking of genotypes based on TOL and STI from GY, respectively.

Yield response of sugarcane to weather variations in Northeast Andhra Pradesh, India

The influence of the meteorological parameters: maximum and minimum temperatures, relative humidity, rainfall and duration of sunshine, on sugarcane yield, is studied by fitting third-degree response function models using the long-period experimental data at the Regional Agricultural Research Station at Anakapalle (17°38′N, 83°01′E), Andhra Pradesh, India. These models give the quantitative response in the yield brought about by a unit change in the meteorological parameters at each stage of the crop growth. The maximum and minimum temperatures and relative humidity during the first three months of the crop (germination and tillering phases), are found to have a profound influence on the yield. Above normal temperatures and drier conditions at this time seem to be favourable for good yields. Presuming that the year-to-year variations of the meteorological parameters are largely the reflections of the broad synoptic systems prevailing over and around the area of study, an attempt has been made to identify the macrometeorological situations that critically affect the sugarcane yield. This is accomplished through selected case studies of weather situations during the critical periods obtained above, for some poor-yield and good-yield years. This study helps in fixing the favourable and unfavourable macrometeorological systems, which could be useful for issuing special agrometeorological forecasts for sugarcane growers and crop-outlook statements.

Comparative Growth-rates of Upland and Swamp Rice Varieties

The growth of swamp rice (Dima) and upland rice (Kindinga) was studied under tropical glass-house conditions in Trinidad. Kindinga ultimately attained greater dry weight and height than Dima but the total number of leaves and tillers per plant were greater in Dima than in Kindinga. Kindinga had a greater number of leaves, on the main shoot, than Dima. Growth curve of leaf-lamina area per plant was similar to that of leaf-lamina dry weight in both varieties but leaf area per unit dry weight of lamina and per plant were usually greater in Kindinga than in Dima. Over the whole period, the mean relative growth rate, leaf weight ratio were greater in Kindinga than in Dima but net assimilation rate was greater in Dima than in Kindinga. Total nitrogen content was greater in Dima than in Kindinga during the tillering period but later the reverse was the case. The rate of nitrogen absorption was high in both varieties during the tillering and reproductive phases. Split applications of nitrogenous fertilizer are therefore suggested. The rate of nitrogen absorption was, however, greater in Dima than in Kindinga during the tillering period and latter half of the reproductive phase.