Herbage Production Research Articles

Эколого-биологические аспекты кустарниковой мелиорации деградированных пастбищ на бугристо-увалистых комплексах песчаных земель Прикаспия

The article presents the results of studies of the effectiveness of shrub reclamation on pastures of the Caspian Sea. Introduction. As a result of the outbreak of deflationary desertification of lands that occurred on the territory of the Russian Caspian Sea in the 70-80-ies of the XX century, it became necessary to develop methods for large-scale shrub reclamation of degraded lands. One of the problematic areas where these works were carried out is pastures on light soils of the Astrakhan Volga region. Materials and methods. The study is based on biomonitoring materials and field experiments using standard methods of forest taxation, soil science and geo-botany. Results and discussion. Thanks to the microclimate, the best conditions for the growth of herbaceous vegetation are formed in the spaces between pasture-protective strips with a width of 30 m. The yield of herbage phyto mass on them, both in spring and autumn, is higher by 0.06–0.13 t/ha. With severe damage or destruction of shrub plantations, areas with productive herbage degrade. Reclamation and forage plantations, depending on the age, increase the yield of pastures by 41–85%. The productivity of herbage is everywhere higher on pastures with a complex of pasture-protective and reclamation-forage plantations with teresken at the age of 20-25 years. Сonclusion. It has been established that pasture protection strips from haloxylon, reclamation and fodder plantations from krascheninnikovia and calligonum in the Astrakhan Volga region have been functioning for more than 45 years. It was determined that in forested areas, depending on age, the preservation of saxaul is 14–45% with an average plant height of 2.0–3.2 m. It is shown that the plantings of krascheninnikovia and calligonum on hollow-bumpy and withered plains with light soils at the age of 30–40 years have a safety of 45–70%, have a positive effect on the restorative succession of herbage between rows of shrubs and in the wind-shade zones of strip and backstage plantings. It was revealed that the addition to the pasture forage in the form of an available twig-leaf mass of shrubs in May – August can reach 0.5–4.0 t/ha in dry form. The hay yield of natural forage vegetation under the protection of shrub plantations on improved pastures is 1.2–1.5 times higher compared to unprotected lands and amounts to 0.70–1.60 t/ha. The results of the research can be useful in the phyto-melioration of degraded pastures located on bumpy sandy lands. Suggestions for practical application and direction of future research. The results of the research can be useful in the phytomelioration of degraded pastures located on bumpy sandy lands. An urgent problem remains the development of a system of measures for the care, repair and reconstruction of shrub plantations that can increase their productivity and durability on functioning pastures.

Agronomic performance of summer forage crops on a Waikato dry-stock farm

Forage crops options are required by dry-stock farmers to fill summer feed gaps. This trial compared a brassica monoculture with simple and hyper-diverse mixtures containing up to 21 forage species sown in October on a Waikato dry-stock farm. Two of the twelve treatments were established at paddock scale. Species included rape, oats, plantain and red clover. Seedling emergence was assessed four weeks after sowing and herbage production, metabolisable energy and botanical composition in mid-January. Rape was common in all mixtures for the provision of high-quality forage. Oats suppressed rape production, even at low sowing rates (<13 kg/ha), and reduced weed ingress. Plantain, sown at <2 kg/ha, contributed negligible dry matter in mid-January but provided ground cover and additional forage by late February. Red clover failed to establish. Most diverse treatments provided a similar energy yield (MJ ME/ha) to rape. Simple mixtures and hyperdiverse mixtures were similar for most metrics. Results at plot and paddock scale were consistent for the energy yield effects. When these data were combined withproduction costs, the energy costs were similar for most treatments. The most promising was a rape dominant mixture, with high energy yield, low weed abundance and low energy costs.

Alternative hormone-free reproduction management of a dairy sheep flock disrupts the farm's annual feeding system calendar and its associated strategies

Hormone-free (HF) reproduction in dairy sheep is a way to meet current societal demands, but it requires being prepared for collateral impacts on related system components. The efficiency of HF practices (e.g., using the male effect for estrus induction and synchronization) is uncertain compared with hormonal treatment (HT). For example, these practices can lead to higher variability in the flock physiological stage patterns throughout the year, which has direct consequences for feeding regimens. The objective of this work was to simulate the impacts of HF reproduction management, including artificial insemination (AI), on the temporal distribution of productive performance and nutritional requirements of a conventional dairy sheep flock. Using the REPROsheep2.0 model, 6 scenarios were compared over one typical production season for the same flock (n = 597 Lacaune ewes) intensively reared in the Roquefort region of France. These scenarios depicted reproduction with HT and AI in mid-May (Early); HT and AI in July (Summer Late); HT and AI in November (Autumn Late); and their HF versions (HF-Early; HF-Summer Late, and HF-Autumn Late, respectively). In all HF scenarios, a reduction in the number of ewes lambing and consequently in the annual milk production of the farm was observed (-1 to -7%). This affected annual performance with a subsequent decrease of total annual nutritional requirements (-2 to -6%). The HF scenarios resulted in a staggering of lambing events with a 7- to 14-d shift in the appearance of milk production peaks and related nutritional requirements compared with the HT scenarios. Transitioning from conventional to HF reproduction management, while preserving AI, would increase farm workload, lengthen milking period operations, and necessitate a readjustment of feeding management strategies with regard to available feed resources. Depending on the production season, the observed delay in the distribution of nutritional requirements could be either an attractive or an unfavorable outcome for farmers. The delay may be concordant, for example, with the recently observed impacts of climate change on seasonal forage availability in Mediterranean regions (less spring herbage production and warmer temperatures) that are affecting farmers' decision-making about the most efficient use of forage and feed resources.

Herbage production and growth performance of late-maturing suckler-bred steers grazing grass- clover or multi-species swards

Herbage production and growth performance of late-maturing suckler-bred steers grazing grass- clover or multi-species swards

Effect of pre-grazing herbage mass and post-grazing sward height on herbage production and intake and performance of suckler-bred steers within a weanling-to-beef production system

AbstractThe current study investigated the effects of pre-grazing herbage mass (PGHM, 1500 or 2500 kg dry matter (DM)/ha) and post-grazing sward height (PGSH, 4 or 6 cm) on herbage production and its nutritive value and DM intake, grazing behaviour and growth of Charolais steers (n = 96; 12 months of age; 396 ± 19.0 kg) during a 222-day grazing season, and the subsequent effect of an indoor finishing diet (grass silage alone or supplemented with concentrates) for 146 days, on performance and carcass traits. Steers were assigned to one of 12 grazing groups and group was assigned to a 2 (PGHM) × 2 (PGSH) factorial arrangement of treatments. At the end of the grazing season, live-weight was 16 kg heavier for PGHM-1500 than PGHM-2500 and 34 kg heavier for PGSH-6 than PGSH-4. After indoor finishing, there was no difference in carcass weight between PGHM treatments, but PGSH-6 had a 19 kg heavier carcass than PGSH-4. Herbage production was 881 and 517 kg DM/ha greater for PGHM-2500 than PGHM-1500 and for PGSH-4 than PGSH-6, respectively. Grazing stocking rate did not differ between PGHM treatments but PGSH-4 carried 1.35 more steers/ha than PGSH-6. Supplementing concentrates during the indoor period increased carcass weight (42 kg) and fat score (2.10 units). In conclusion, grazing to 6 rather than 4 cm, increased individual carcass weight but not carcass weight gain/ha. Compared to PGHM-2500, grazing PGHM-1500 increased steer live-weight gain at pasture, but did not affect carcass weight following indoor finishing.

Maintaining scattered trees to boost carbon stock in temperate pastures does not compromise overall pasture quality for the livestock

Scattered trees in wood-pastures represent outstanding conservation value by providing microhabitats for a variety of organisms. They also diversify ecosystem services by creating shade for livestock, and capturing and storing carbon. However, trees in wood-pastures are declining Europe-wide and an appropriate legal environment to maintain them is mostly lacking. Here we looked beyond the well-documented beneficial effects of trees and assessed potential ecosystem disservices, which may drive the controversial appreciation of trees. In a grazing exclusion experiment, we assessed the effect of trees on herbage production in wood-pastures from semi-arid continental to humid montane areas in the temperate deciduous forest ecoregion, and found that trees have a suppressive effect throughout the year, although herbage nutritive value, as indicated by herbage nitrogen content, seems to be improved in spring. When we up-scaled the local ecosystem disservice on herbage yield to entire wood-pastures, the loss remained below 3%, which is lower than reported gains in livestock production due to free access to shade. Thus, the motivation for the under-appreciation of trees by land managers and decision makers may lie in that trees suppress herbage production, but the importance of this effects is offset by the magnitude of the beneficial services of trees. We recommend current wood-pasture stakeholders to revisit their attitude towards scattered trees and encourage tree planting campaigns and tree-based climate mitigation strategies to consider the protection of trees in wood-pastures and the establishment of young ones in currently open pastures up to traditionally low tree cover proportions, as livestock production is unlikely to be compromised by this action.

Mixtures of grasses: An alternative to traditional pasture monocultures in the tropics

AbstractA two‐year experiment assessed herbage production and above‐ and below‐ground characteristics of a highly productive monoculture (‘BRS Zuri’ guineagrass [Panicum maximum Jacq.]) and two mixtures of three grasses (Mixture 1: ‘BRS Zuri’ guineagrass, ‘BRS Xaraés’ palisadegrass [Brachiaria brizantha Stapf.], and ‘Basilisk’ signalgrass [Brachiaria decumbens Stapf.]; Mixture 2: ‘BRS Quênia’ guineagrass [Panicum maximum Jacq.], ‘Marandu’ palisadegrass [Brachiaria brizantha Stapf.], and ‘BRS Paiaguás’ palisadegrass [Brachiaria brizantha Stapf.]), cultivated in the Brazilian tropical savanna. Mixtures 1 and 2 were subjected to two grazing intensities (removal of 40 or 60% of pre‐grazing height) and ‘BRS Zuri’ guineagrass monoculture was defoliated to a single grazing intensity of 50%. Treatments were randomly assigned to fifteen 0.25‐ha plots and managed under intermittent stocking by cattle. Herbage accumulation rate was similar among pastures and years (p > .1). The root mass in the tussocks did not differ (p > .1), with mean values ranging between 0.62 to 1.81 kg DM m−2. Root density in the tussock interspaces was greater in the mixtures (p < .001), regardless of seasons (p = .405) and years (p = .292). The mixtures were dominated by guineagrass (70%) and palisadegrass (30%) at the end of the experiment, with the population of ‘Basilisk’ and ‘BRS Paiaguás’ being completely suppressed throughout the experimental period. Mixing guineagrass and brachiariagrasses can be an alternative to the traditional pastoral systems in the tropics, as it does not compromise herbage production and presents a capacity to produce more roots than a very productive monoculture of ‘BRS Zuri’ guineagrass.

The results of a field experiment on the influence of corn seed soaking on the herbage grown for silage

Background: The assuring of simultaneous and quick seedlings is one of the tasks by the cultivation of agricultural crops. Seed priming is a simple way of the influence on the germinating capacity and productivity of young crops. Methods: During the research process the influence of seed soaking in water and potassium humate on the productivity of corn herbage was evaluated. The seeding was carried out with a single-row seed-metering device by randomization of working plots. The received results were evaluated by a statistic method of data processing. Result: By the statistic data processing it was determined that with a probability of 95% soaking in the solution of potassium humate during 30 hours gave the 16.5 % increase of the average mass of all stalks (caules), and the soaking in water during 36 hours with a probability of 95% led to the 20.5% increase of the average mass of all stalks. The received results allowed drawing a conclusion that priming gives a positive effect for corn growing in unfavorable climate conditions.

Feed profile analysis of oil palm‐integrated beef cattle farming systems by metabolic energy budgeting and implications for beef production and pastoral system design

AbstractBackgroundOil palm is a tropical crop with worldwide plantings approaching 20 million ha and large areas in Indonesia, Malaysia and Thailand. The plantations are readily managed as silvopastoral systems incorporating cattle grazing (Oil Palm Silvopastoral System for Cattle, OPSC) but there is a need for analytical tools and data to understand system herbage supply and feed conversion efficiency (FCE).MethodsMetabolic energy budgeting was used to estimate herbage harvested by cattle in three OPSC subsystems, 9 and 12 years after oil palm establishment, and FCE of the subsystems was determined. Understorey herbage was also analysed for nutritive value, botanical composition and herbage accumulation within one grazing‐regrowth cycle.ResultsThe herbage‐harvested estimate was 2.0−2.4 t dry matter (DM) ha−1 year−1 for 9 year old subsystems and 1.4−1.7 t DM ha−1 year−1 for a 12 year old subsystem. Herbage metabolisable energy (ME) was 8.3−8.5 MJ kg−1 DM and crude protein (CP) was 15%−16% DM. FCE values for subsystems ranged from 32 to 94 kg DM kg−1 liveweight‐gain.ConclusionsHerbage DM yield is declining, while herbage ME is marginal but CP is adequate. FCE is suboptimal but can be optimised by defining the trajectory of declining herbage production with canopy closure as plantations age and matching stocking rate to herbage supply using a comparative‐stocking‐rate‐type statistic.

Can a urease inhibitor improve the efficacy of nitrogen use under perennial ryegrass temperate grazing conditions?

AbstractThis study sought to compare the efficiency of different nitrogen (N) fertilizer forms applied to perennial ryegrass swards that were rotationally grazed by dairy cows or sheep under Irish conditions for two or three years. A 3 × 2 factorial random complete block design plot arrangement was used to compare calcium ammonium nitrate (CAN), urea and urea + N-(n-butyl) thiophosphoric triamide (urea + NBPT) at 150 and 250 kg N/ha per year. Zero nitrogen plots were also added to allow for N efficiency to be calculated. The study was conducted at four sites, giving three years of data collection at two sites and two years at the other two sites. All four sites observed similar responses to N fertilizer type and N fertilizer rate. Significant differences were observed between the 150 kg N/ha and 250 kg N/ha treatments for pre-grazing herbage yield (1346 and 1588 kg DM/ha, respectively; P < 0.001) and total herbage production (12 290 and 14 448 kg DM/ha, respectively; P < 0.001). There was no difference but a tendency for pre-grazing herbage yield to be higher for CAN and urea + NBPT than urea (1485, 1480 and 1436 kg DM/ha, for CAN, urea + NBPT and urea, respectively; P = 0.091). Total herbage production was significantly higher for CAN and urea + NBPT than urea (13 478, 13 542 and 13 087 kg DM/ha, respectively; P = 0.004). In conclusion, there was an overall benefit detected over the 10 site-years from using urea protected with NBPT v. using urea.

Comparative analysis of prospect corn varieties productivity under high-risk farming Amur river region area

The article presents the results of the results of the study of corn hybrids of various ecological and geographical origin according to economic traits. The research was carried out during 2019-2021 in the nursery of the competitive variety trial of the fodder production department on the experimental plot of vegetable rotation of the Far Eastern Agricultural Research Institute (FEARI) by the method of agro-climatic analogues as applicable to the extreme conditions of the Khabarovsk territory. The targets of research were 28 maize hybrids, 16 of which were selected by FEARI. The goal of research is сomparative assessment of the productivity of promising corn hybrids in conditions of risk farming zone in the Amur river region. The studied hybrids were divided into 2 groups: short-season hybrids (FAO - 150-199), 13 samples. The standard is the local selection Birsu hybrid. 2. middle-early hybrids (FAO - 200-299), 15 samples. The standard is released in the Khabarovsk territory Moldavian 215 SV hybrid. On average during the research period the grain productivity of most of the samples in the group of short-season hybrids didn’t exceed the characteristics of standard hybrid. Only Birsu (2-cob) hybrid stood out (+12.4 dt/ha). In terms of herbage and cob productivity almost all hybrids exceed the standard values (Birsu - 194,8; 106,6 dt/ha) by 9.7-126.2 and 9.0-29.49 dt/ha respectively. In the group of middle-early hybrids the Porumben 295 ASV x fertile restorer hybrid stood out. In terms of grain, herbage and cob productivity it exceeded the standard hybrid Moldavian 215 (59.7, 256.9, 110.4 dt/ha) by 31.7, 113.7 and 59.2 dt/ha respectively. Based on the research findings the selected by FEARI Alitet 2 advantageous hybrid was marked out. In terms of herbage productivity it exceed Birsu hybrid by 54.3% and in terms of cob productivity - by 26,1%. The hybrid is transferred to the state variety testing.

Spatial variability of herbage yield, grazing capacity and plant diversity in a tropical savannah rangeland ecosystem

To improve ruminant livestock production, evaluation of rangelands must be a routine. Rangeland evaluation gives information about the vegetation structure, biomass yield and quality. The Guinea savannah rangelands of Ghana lack research that characterises the spatial variability of herbage yield and quality. It was hypothesised that there is spatial heterogeneity in herbage yield, grazing capacity and plant diversity in the Guinea savannah rangelands of Ghana. The objective was to evaluate the spatial structure of herbage production and grazing capacity in the Guinea savannah rangelands of Ghana for sustainable livestock production. Data were collected from 105 sampling sites and integrated into geo-statistics, using ordinary kriging interpolation to generate herbage yield and grazing capacity estimates. Herbage yield and grazing capacity ranged from 0.63 t ha−1 to 13.43 t ha−1 and 0.18 LU ha−1 to 3.79 LU ha−1 respectively. The root mean square error and the average standard error values were close (2.38 and 2.51 respectively for herbage yield and 0.67 and 0.71 respectively for grazing capacity). Species diversity using the Shannon’s index ranged from 1.13 to 2.40. There was spatial heterogeneity in herbage yield, grazing capacity and species diversity in Ghana’s Guinea savannah rangelands with some parts needing effective site-specific improvement strategies for sustainable livestock production.

Production characteristics of red napier grass (Pennisetum purpureum cv. red) on different combination of soil and vermicompost as planting media

This study aimed at measuring production characteristics of Red Napier grass grown on planting media comprising different combinations of soil and vermicompost. The experiment was executed in greenhouse following completely randomized design with 5 treatments i.e. T0: 100% soil (control), T1: 75% soil + 25% vermicompost, T2: 50% soil + 50% vermicompost, T3: 25% soil + 75% vermicompost and T4: 100% vermicompost. Each treatment was replicated 5 times. The soil and vermicompost proportion were from 20 kg total planting media filled in polybags on which the grass stem cuttings were planted. Harvest was done 90 days after planting. Collected data were subjected to analysis of variance and least significant difference test. The results showed that treatments did not significantly affect (P>0.05) plant height, but significantly affect (P<0.05) leaf to stem ratio and very significantly affect (P<0.01) number of tillers, number of leaves, and nutrient production of stem, leaf and herbage. Highest production of dry matter was obtained at the treatment of T3.

PRODUKSI HIJAUAN DAN KOMPOSISI KIMIA RUMPUT KUME DAN SUKET PUTIHAN YANG DIINTRODUKSI JENIS LEGUMINOSA BERBEDA (Herbage production and chemical composition of kume grass and suket putihan introduced with different types of legumes)

Low quality and quantity of pasture in East Nusa Tengara is the main problem in development of ruminants. The solution offered to this problem is by using mixed pasture of grass and legume, by consider legume’s advantage in nitrogen fixation, and also it’s capability to provide canopy or shades to grass. The aim of this experiment was to investigate the effect of the introduction of various species of herbaceous legumes on herbage production and the chemical composition of Sorghum plumosum and Bothriochloa pertusa. The research was conducted following a Completely Randomized Design (RCD) with 4 treatments and 3 replications. The treatments tested consisted of Co (Sorghum plumosum and Bothriochloa pertusa), Av (Sorghum plumosum, Bothriochloa pertusa and Alysicarpus vaginalis), Ct (Sorghum plumosum, Bothriochloa pertusa and Clitoria ternatea) and Pp (Sorghum plumosum, Bothriochloa pertusa and Pueraria phaseoloides). The parameters observed were the production of forage, the leaf stem ratio, crude protein, crude fiber, and NDF (Neutral Detergent Fiber). The results showed that the introduction of herbaceous legumes did not affect the production, leaf stem ratio and also the crude protein but does affect the chemical composition of Kume and Suket Putihan such as changes of crude fibre and NDF at the age of 60 days.

Production and Commercialization Status of Improved Panicum Grass Cultivation in the Lowland Livestock Production System of South Omo South-Western Ethiopia

Lack of information on the production and commercialization status of improved Panicum grass is one of the major livestock production impediments in South Omo. The improved Panicum grass is a perennial grass species used throughout the tropics for livestock feeding. Therefore, the present study was conducted to understand the seed and hay production status and the economic visibility of improved Panicum grass cultivation. The face-to-face interviews were conducted with improved Panicum grass producers. The quantitative data, such as the amount of bales and seed produced, and the qualitative data, such as agro-pastoralists’ perceptions, were analyzed using simple descriptive statistics and the Likert scale. The results revealed that the seed yield and herbage productivity after seed harvest were 2.5 quintals and 788 bales per hectare per cut, respectively. The average income generated from the sale of herbage and seed of Panicum grass was 325,350 ETB and 442,500 ETB per hectare per year, respectively. Based on the results, the authors concluded that joint efforts are needed to step the agro-pastoralists out of the poverty vicious cycle through promoting wide-scale improved Panicum grass production by linking products to market sources in addition to legumePanicum grass-based cattle and goat fattening intervention.

Monthly mowing frequency does not affect soil CO2 emissions of fertilized Bromus erectus‐dominated grasslands

AbstractSecondary origin grasslands are widespread habitats that provide a wide array of ecosystem services. Their conservation relies on management practices that can, in turn, alter their soil carbon cycle to result in higher soil respiration rates. In the perspective of social and climate change scenarios, there is the need to seek the best management practices for conservation of secondary origin grasslands, climate mitigation and economic sustainability for farmers. The aim of this study was to investigate whether increasing the customary practice of mowing twice a year to monthly mowing through the growing season (when herbage production was feasible; i.e., >0.5 t/ha dry matter) generates changes to the drivers and rates of soil respiration of fertilized Bromus erectus‐dominated grasslands. Soil CO2 efflux, temperature and moisture were recorded over 3 years (2016–2018) under these “customary” and “monthly” mowing frequencies (twice per year; 4–6 times per year, respectively). Soil CO2 efflux, temperature and moisture were not affected by the higher mowing frequency over the study period. Independent of mowing frequency, soil water content was the main driver of soil CO2 emissions during the growing season (April to October, inclusive), whereas soil temperature was the main driver during the nongrowing season (November to March, inclusive). Therefore, increasing the customary mowing of twice a year to the monthly mowing frequency through the growing season does not impact upon soil respiration of B. erectus‐dominated grasslands, at least over a 3‐year period.

Anthropogenic dark earth: Evolution, distribution, physical, and chemical properties

AbstractAnthropogenic dark earth (ADE) is a category of Anthrosols (anthropogenic soils) characterised by dark colour from homogeneous charcoal inclusion and extraordinary fertility compared with non‐anthropogenic soils. The study aims to provide a detailed overview of the origin and distributions of ADEs, together with their physical and chemical characteristics, to reveal their fertility status for arable land use. According to this study, most studied ADEs are well distributed in tropical (Amazonian and African dark earth) and temperate (European dark earth) climatic regions. Middens are localised, with large‐sized ones well preserved in the Arctic region due to the wet and cold weather conditions. The formation of ADE is mainly associated with deliberate and unintentional ancient human activities: deposition of domestic and occupational wastes, charred residues, biomass ashes, burning, and fertilisation of fields. The characteristic dark colour of ADE resulted mainly from charcoal and the decomposition of organic wastes. The material composition of ADEs (including charcoal, organic matter, and clay) contributes to the formation of sizable pores for the retention of water and elements and aeration. ADE exhibits a C:N ratio for good mineralization, stable organic matter stock, and higher cation exchange capacity. Additionally, ADEs are characterised by circum‐neutral reactions and enriched by nutrients (C, N, P, Ca, Mg, Mn, Cu, Zn, Mn, and Fe) and other elements (Sr, Rb, and Ba) compared with surrounding non‐anthropogenic soils. Although generally highly productive, a comparison of herbage production and crop yields between ADEs and natural soils is not well studied. The persistence of anthropogenic activities that lead to the formation of ADE indicates that these soils are still subject to continuous development, especially in rural settings. Adopting the process of ADE development in recent arable land can represent a promising future for sustainable agriculture.Highlights Anthropogenic dark earths (ADEs) are characterized by their physical and chemical signatures. Characteristic high pore size of ADEs due to charcoal inclusion support the retention of nutrients. ADEs are often have reduced acidity and high C, N, P, Ca, Mg, Mn, Cu, Zn, Mn, and Fe contents. ADEs represent an archive of fertile soils suitable for sustainable agriculture.

The Physiological Role of Abscisic Acid in Regulating Root System Architecture of Alfalfa in Its Adaptation to Water Deficit

Alfalfa (Medicago sativa L.) is a perennial leguminous plant, with a strong tap root system that plays an important role in alfalfa’s adaptation to drought stress. However, a better understanding of root functional traits and how these root traits are related to whole plant responses in order to improve pasture productivity under water deficit. Two greenhouse experiments were conducted: Experiment 1 used three alfalfa cultivars and four levels of soil water content treatments to investigate herbage productivity, growth point density, residual shoot weight, and root weight. Experiment 2 assessed relationships among root-sourced abscisic acid (ABA), root system architecture and plant biomass in response to water deficit. The results demonstrated that root system was used as a useful tool to improve tolerant and adaptation when alfalfa copied with lower levels of soil water content. On average, maintaining 60–65% soil water-holding capacity alfalfa had the highest herbage accumulation (6.7 g DM pot-1), growing point density (46.5 pot-1), and residual shoot biomass (1.8 g DM pot-1). At the level of water stress, Medicago sativa L. cv Zhaodong (ZD) and cv Aohan (AH) tended to exhibit a herringbone branching pattern with less root tips, root forks, altitude, and magnitude than cv Golden empress (GE). Principal component analysis and structural equation modeling revealed that root-sourced ABA positively regulated the altitude and magnitude of root system architecture, root tips and root forks, and was closely associated with plant root biomass and herbage biomass. It was concluded that these findings can contribute to developing optimum irrigation strategies and help alfalfa breeders in the development of new cultivars with improved drought tolerance based on root system architecture, plant hormone, and plant growth.

Effect of Defoliation Age on The Production and Energy Value of Indian Bluegrass (Bothriochloa pertusa)

The purpose of this experiment was to evaluate the herbage production and energy value of Suket putihan grass (Bothriochloa pertusa) harvested at different ages. The experiment was carried out following a completely randomize design with 3 treatments and 3 replications. The treatments consisted of different defoliation ages of Suket putihan grass (Bothriochloa pertusa), i.e. respectively at 40 days (BP40), 60 days (BP60), 80 days (BP80). The observed variables included the dry matter (DM) production, stem leaf ratio, In vitro digestibillity and energy value. Result showed that the defoliaton age had a significant effect (P<0.05) on dry matter production, stem leaf ratio, dry matter digestibillity and had a very significant effect (P<0.01) on the organic matter digestibillity and energy value of Suket putihan grass (Bothriochloa pertusa). The DM production of Suket Putihan grass (Bothriochloa pertusa) increased with increasing defoliation age, while its In vitro digestibility and energy value decreased due to the high stem to leaf ratio and increased harvesting time. In conclusion, the best defoliation time for B. pertusa is between 40 and 60 days after planting.

The influence of phosphorus application and varying soil pH on soil and herbage properties across a range of grassland soils with impeded drainage

AbstractOn soils dominated by high proportions of clay and organic matter, soil acidity and poor nutrient use efficiency have a major impact on output potential. Due to the inherent chemical properties of these soils, reducing soil acidity and the prevalence of undesirable metallic cations poses challenges. As a result, these soils have a large capacity for phosphorus (P) fixation, therefore reducing plant P availability. Limestone (CaCO3or MgCO3) is applied to agricultural soils to counteract soil acidity and reduce P fixation. The current study investigates the effects of four contrasting annual P application rates (0, 50, 100, 150 kg P/ha); split (50:50) between spring and summer, across soils with a range of soil pH values from a previous liming trial. The effect of soil pH ranges and P treatment rates on seasonal herbage growth and herbage P concentration was investigated over three years. Soil nutrient status was also investigated. Soil pH had a significant impact on the rate of mineralization and soil P concentration across each site. A soil pH of 6.2 caused a 1.8 mg/l increase in soil test P. An annual P application was necessary to maintain sufficient herbage P concentration for animal dietary requirements (0.35% DM), however there was no effect of P application or liming rate on herbage productivity across the three sites as all sites possessed sufficient soil P reserves. The current experiment has shown that despite optimal soil fertility status, ensuring sufficient plant available P is a problem on these particular soils.