Influence of cutting management on photosynthetic parameters, heat use efficiency and productivity of barley (Hordium vulgare L.) under variable sowing dates

Field experiments were conducted during 2015–16 and 2016–17 at Punjab Agricultural University, Ludhiana, to study the effect of staggered sowing on photosynthetic parameters, heat use efficiency and the productivity of barley (Hordium vulgare L.) in relation to different cutting management. The experiment was laid out in split plot design with three sowing dates (October 15, October 30 and November 15) in main plots and five cutting management [un-cut (control), cut at 50 days after sowing (DAS), cut at 60 DAS, cut at 50 DAS + additional 15 kg N ha-1 after cut (N15) and cut at 60 DAS + additional 15 kg N ha-1 after cut (N15)] in sub plots,replicated four times. The results indicated that photosynthetic parameters (PAR interception, chlorophyll index and normalized difference vegetation index) decreased significantly and progressively with each delay in sowing. Heat use efficiency and helio thermal use efficiency of October 15 and October 30 sown crops were statistically similar. Delay in sowing caused significant reduction in fodder, grain and biological yield of barley probably due to significant reduction in photosynthetic parameters.Nitrogen application after fodder cut improved the chlorophyll index, whereas, cutting did not influence the normalized difference vegetative index (NDVI).Un-cut crop recorded higher PAR interception.Significantly higher heat use efficiency and helio thermal use efficiency were recorded in uncutcrop. Un-cut and fodder cut at 50 DAS produced similar grain and biological yield and significantly higher than other cutting treatments. Cut at 60 DAS gave higher fodder yield but at the cost of 9.43-18.3 per cent reduction in grain yield than cut at 50 DAS. Correlation studies indicated significant positive correlation of grain yield with photosynthetic parameters, emphasizing the importance of higher growth and photosynthetic rate during reproductive period for best yield accrual from barley.

Restoration management of cattle resting place in mountain grassland

This study investigated the effect of restoration management of a weed-infested area, previously used as cattle resting place, on herbage production and nutrient concentrations in the soil and herbage. The experiment was undertaken from 2004 to 2011 at the National Park of Nízké Tatry, Slovakia. Three treatments were applied: (i) cutting twice per year, (ii) herbicide application, followed after three weeks by reseeding with a mixture of vascular plant species and then cut twice per year, and (iii) unmanaged. Treatments had significant effect on biomass production and concentration of nutrients in the soil and in herbage. Nutrient concentrations in herbage and in soil declined progressively under the cutting treatments and reached optimum ranges for dairy cattle at the end of the experiment when herbage N was less than 15 g kg-1 and herbage P was 3.4 g kg-1. There was also a strong positive relationship under the cutting treatments between soil nutrient concentrations and herbage nutrient concentrations for N, P, K, Mg and Ca. Although the cutting management as well as the combination of herbicide application with cutting management reduced nutrient concentrations in the soil and in herbage, the nutrient concentrations remained relatively high. We can conclude that restoration of grassland covered with weedy species like Urtica dioica and Rumex obtusifolius, with excessive levels of soil nutrients, cannot be achieved just by cutting and herbicide application.

Nutritional value of forage mass as affected by cutting management of perennial grasses

Работа проведена в 2016–2018 годах на опытном поле лаборатории агротехнологий «Вилга» отдела комплексных научных исследований КарНЦ РАН. Цель работы — установить оптимальный режим скашивания многолетних травостоев с включением интродуцированных видов кормовых трав, обеспечивающий высокие показатели качества кормовой массы в условиях Карелии. В статье представлены результаты научных исследований по оценке питательной ценности биомассы многолетних агрофитоценозов, созданных с включением интродуцированных видов бобовых и злаковых трав — люцерны изменчивой (Medicago varia Mart.) и фестулолиума (×Festulolium F. Aschers. et Graebn.) при двух- и трёхкратном режимах скашивания. Внесение фосфорных и калийных удобрений в дозе Р60К90 на бобово-злаковых и злаковых травостоях проводили однократно перед завершением вегетации растений. Азотные удобрения (аммиачную селитру) в дозе N120 вносили при формировании злакового травостоя дробно под каждый укос: N60 — при двухукосном использовании и N40 — при трёхукосном. Установлено, что в данных условиях травосмеси кострец безостый + люцерна изменчивая + клевер гибридный и фестулолиум + люцерна изменчивая + клевер гибридный обеспечивали высокий уровень урожайности сухой массы (7,55–9,13 т/га), энергетической продуктивности (79,7–94,7 ГДж/га) и питательной ценности (0,81–1,31 т/га сырого протеина) независимо от режима скашивания. На фоне внесения минерального азота в дозе N120 урожайность злакового травостоя выше бобово-злаковых агроценозов, но показатели питательной ценности не соответствовали нормативам кормления высокопродуктивного крупного рогатого скота. В условиях северного земледелия наиболее целесообразным является двухкратный режим скашивания травостоев в период бутонизации – начала цветения бобовых и колошения злаковых трав. Использование агрофитоценозов с включением многолетних бобовых культур без внесения азотных удобрений способствует получению экологически безопасного высокобелкового растительного сырья для заготовки грубых и сочных кормов. Ключевые слова: многолетние травы, люцерна изменчивая, фестулолиум, питательная ценность, режим скашивания. The experiment was carried out at the “Vilga” laboratory in 2016–2018. The goal was to optimize cutting regime for perennial grasses to obtain high-quality forage mass. This article reports on nutritional value of perennial ecosystems with bastard alfalfa (Medicago varia Mart.) and festulolium (×Festulolium F. Aschers. et Graebn.) to be cut twice or three times. Application of Р60К90 was done once before the end of growing season. N120 was divided into two or three fractions and applied before each cut as N60 or N40 depending on cutting regime. Smooth brome + bastard alfalfa + alsike clover and festulolium + bastard alfalfa + alsike clover produced high yields of dry mass (7.55–9.13 t ha-1), energy (79.7–94.7 GJ ha-1) and had high nutritional value (0.81–1.31 t ha-1 of crude protein) regardless of the cutting regime. On the background of N120 gramineous exceeded gramineous-legume mixtures in productivity but had low nutritional value. Cutting legumes at budding – early flowering and gramineous — at heading time twice was more effective under cold conditions. Growing grass mixtures with perennial legumes without fertilization resulted in ecologically-safe high-protein forage mass.