Total Herbage Yield Research Articles

Effect of Organic Manures on Growth and Yield Attributes of Citronella Java (Cymbopogon winterianus) under Moringa (Moringa oleifera) based Agroforestry and Open-field Systems

A field investigation was conducted to evaluate the effects of farmyard manure (FYM) vermicompost and neem-cake on the growth and yield of citronella java (Cymbopogon winterianus) under moringa-based agroforestry and open-field systems during 2022 and 2023. Growth parameters like plant height, number of leaves per plant and number of tillers per plant and yield attributing parameters like fresh weight (kg ha-1), Dry Weight (kg ha-1) and total herbage yield (t ha-1). The findings highlight the superior performance of the treatment combining FYM, vermicompost, and neem cake (T13), particularly in shaded conditions provided by moringa trees, which created a favourable microclimate. This study demonstrates the significant role of integrated organic amendments in enhancing citronella productivity while fostering environmental sustainability. The findings offer valuable insights for farmers and policymakers, advocating for the adoption of sustainable practices in aromatic crop production through agroforestry systems.

EFFECT OF DIFFERENT PLANT DENSITY ON THE FORAGE YIELD AND SOME FORAGE QUALITY CHARACTERISTICS OF MORINGA (Moringa oleifera Lam.)

In sustainable animal husbandry, the use of highly adaptable shrub and tree species as alternative forage crops has gained importance in recent years. One of these plants is moringa (Moringa oleifera Lam.), which is considered one of the promising feed sources due to its high nutritional value. This research was carried out to determine the potential of Moringa as a forage crop for the Mediterranean climate during 2020 and 2021 growing season in the experimental areas of the Department of Field Crops, Faculty of Agriculture, University of Ege, Türkiye. The effects of four different plant densities (60x20 cm, 60x30 cm, 60x40 cm, 60x60 cm) on the some forage quality and digestibility traits were investigated. The Moringa cultivar "PKM-1" was used as plant material and plant height, stem diameter, dry matter, herbage yield, crude protein, crude ash, crude fat, neutral detergent fiber (NDF) and acid detergent fiber (ADF) were examined during two consecutive vegetation periods. In the study conducted in Mediterranean ecological conditions, the average values of the moringa plant for two years were obtained as Plant height 159.2-170.3 cm, total herbage yield 3.310-6.970 kg/da, crude protein ratio 17.12-18.15%, ADF ratio 35.31-37.85% and NDF ratio 45.66-49.71%. Increasing the planting density increased the herbage yield and the highest value was obtained from 60x20 cm planting density. In addition, 60x20 cm planting density is also suggested in terms of protein , ADF and NDF traits.

Performance of dairy cows offered silages produced from grass swards harvested on either three or five occasions during the growing season

The nutritive value of grass silage can be improved by harvesting herbage at a less mature growth stage, which in practice usually involves more frequent harvests. This study examined the performance of dairy cows offered grass silages produced from perennial ryegrass (Lolium perenne) based swards harvested at 2 different frequencies during the growing season (3-harvest (3H) vs. 5-harvest (5H)). Thirty-four mid-lactation (av. 147 d in milk) dairy cows (30 multiparous, 4 primiparous) were offered either 3H or 5H silages in a continuous design (21 wk) experiment. Within each treatment cows were offered silage from each harvest (in harvest number order) for a pre-determined number of days in proportion to herbage DM yield at each harvest. Silages were offered ad libitum while a common concentrate was offered to all cows at 12.0 kg per cow/d over the first 15 wk of the study, 8.0 kg per cow/d during wk 16 -19 and 6.0 kg cow/d during wk 20 - 21. Total yield of herbage harvested over the season from within 3H and 5H were 12.6 and 11.2 t DM/ha, respectively. Across all harvests the mean ME and CP concentration of silages were 10.9 MJ/kg DM and 131 g/kg DM for 3H, and 11.5 MJ/kg DM and 152 g/kg DM for 5H. Silage DMI was greater for cows offered 5H silages compared with 3H silages (14.1 vs. 11.7 kg/d, respectively). Cows offered 5H silages had a greater daily milk yield (33.5 vs. 31.9 kg) and ECM yield (37.4 vs. 35.6 kg) compared with cows offered 3H silages. Treatment had no effect on milk fat or protein concentration. Cows offered 5H silages produced milk with greater concentrations of CLA and n-3 fatty acids. Treatment had no effect on mean BW or BCS, or on efficiency metrics such as milk yield or ECM yield per kg of DMI. Molar proportions of VFA in ruminal fluid differed between the treatments, with cows offered 3H silages having higher proportion of total butyrate (15.9 vs. 14.4% of total VFA) and lower total valerate (3.2 vs. 3.7% of total VFA) compared with those offered 5H. The acetate: propionate and acetate plus butyrate: propionate ratios were unaffected by treatment. In conclusion, increasing herbage harvesting frequency from 3 to 5 times per year improved the nutritional value of the resulting silages, and this led to higher silage DMI, milk yield and ECM yield. However, overall production efficiency (ECM/DMI) was unaffected by treatment.

Biostimulant effects on the herbage yield and nutritive composition of a mixed ryegrass–clover pasture

Dairy producers are continuously searching for environmentally friendly and economically sustainable alternatives to increase pasture herbage yield and reduce reliance on chemical fertilisers. A possible means to reduce fertiliser reliance is the use of biostimulants. Biostimulants such as fulvic acid and bioflavonoids help to increase N uptake efficiency, thereby increasing herbage quantity and quality. The aim of this study was to determine the effects of a soil application of a carbohydrate-derived fulvic acid and bioflavonoid biostimulant on herbage yield and nutritive composition of a mixed perennial ryegrass–clover pasture. Biostimulant treatment resulted in a lower ryegrass component of the mixed sward, in both winter and summer grazing cycles. However, the nutritive composition and total herbage yield of the pasture were not significantly affected by biostimulant treatment. The treatment did show a tendency to affect total herbage yield within a season. This suggests that total herbage yield could be increased if additional N fertiliser is applied together with a biostimulant soil treatment, although further investigation is needed to confirm this postulation. Biostimulant treatments have the potential to lead to reduced fertiliser inputs on perennial ryegrass–clover pastures as they may increase nutrient uptake efficiency.

IMPACT OF ORGANIC AND BIOFERTILIZER APPLICATION ON YIELD AND YIELD ATTRIBUTING CHARACTERS IN LINSEED (Linum usitatissimum L.)

Linseed (Linum usitatissimum L.) belongs to family Linaceae, is the second most important rabi oilseed crop and stands next to rapeseed – mustard in area of cultivation and seed production in India. Flaxseed is grown as either oil crop or a fibre crop with fibre linen derived from the stem of fibre varieties and oil from the seed of linseed varieties. Several studies have been conducted on effect of fertilizers on growth and yield of linseed (Linum usitatissimum L.) varieties which revealed their enhancing role on the quality and quantity of flax cultivars. In this regards, a present study was planned and conducted during the Rabi season of 2020-2021 in the Agricultural field of School of Agricultural Sciences, Shri Guru Ram Rai University, Dehradun, Uttarakhand, India to investigate the effect of organic and biofertilizer and integrated treatment on the growth and yield of Linseed. The findings were reported on important growth and yield attributed parameters such as plant height, total fresh weight, total yield, 1000- seed weight (g), and number of seed / capsules. The maximum growth and yield was reported in T6 treatment where biofertilizer have been applied in consortium form followed by vermicompost. Thus, the findings revealed that all the microbial strains in consortia used as bio fertilizers showed enhanced tern of vegetative growth of plants, total herbage yield and total seed yield at various stages. This may be due to sustained release of nutrients to supply the required elements in microbial strains. The biofertilizers exhibited beneficial effects on plant growth and development either through producing growth hormones like IAA, kinetin and gibberellins, synthesizing atmospheric nitrogen and its increased availability to greater protein synthesis as well as increasing Phosphorus availability to plant communities. Thus, it was concluded that the enhanced expression of yield and its related attributes will have beneficial impact in production of nutraceutical products of commercial importance.

Effect of cutting frequency and nitrogen application on herbage yield and nitrogen content of a degraded Panicum maximum pasture.

The effects of cutting frequency and levels of nitrogen on revitalization of a run-down pasture were investigated in 2000 and 2001 at Nsukka, Nigeria. Grass swards were cut at intervals of 3, 6, 9 and 12 weeks and received 0, 150, 300 and 450 kg N ha' nitrogen. Grass dry matter yield was increased from 52 to 75% at the 3 and 6 weeks intervals of cutting, respectively. Weed proportion was reduced from 48 to 25% with 6-weekly cuts compared with more frequent cutting at 3 weeks interval between cuts. Cutting interval did not affect the total herbage yield. The dry matter yields of leaf blade, stem and inflorescence fractions increased significantly with increase in interval between cuts in the second year. The percentage nitrogen content was highest with 3-weekly interval of cut and decreased with high interval of cuts in the second year. Crude protein yield (kg ha') was highest with 6- and followed by 3- and 9-weekly intervals of cut and decreased with lar cutting of 12-weekly interval. Fertilizer-N treatment significantly increased total annual herbage dry matter yield from 3,460 kg ha yrl where no fertilizer N was applied to 5,233 kg ha-yr' with application of 450 kg N ha-'. Grass dry matter as proportion of the total herbage dry matter was increased from 57 to 80% with the highest N rate of 450 kg Nha compared with where N was not applied, while the weed dry matter as proportion of the total herbage dry matter was reduced from 43 to 20% with the highest N rate of 450 kg N ha compared with where N was not applied at the second year. A combination of 6-weeks interval of cutting with 450 kg N ha' gave the highest dry matter yield. It was also adequate in suppressing weed. Frequent cutting at higher levels of fertilizer N (300 - 450 kg ha'') increased the nitrogen and crude protein percentages of forage foliage while 6-weekly interval of cuts when combined with higher N levels gave the highest crude protein yield per hectare per year in the foliage herbage.

Greenhouse Gas Emissions from Cut Grasslands Renovated with Full Inversion Tillage, Shallow Tillage, and Use of a Tine Drill in Nasu, Japan

To restore the productivity of a deteriorated sward due to weed invasion, renovation (re-sowing) is necessary. However, the renovation method used can affect the sward’s greenhouse gas (GHG) emissions and herbage yield. This study compared the effects of renovation using full inversion tillage (F), shallow tillage (S), or a tine drill (T) on the GHG emissions and herbage yield of a grassland in Nasu, Japan. Two adjacent grasslands were renovated in September 2015 (year 1) and 2016 (year 2). In each year, F, S, and T plots (5 m × 20 m each) were arranged in a randomized complete block design with four replications and then orchardgrass (Dactylis glomerata L.) was seeded. All plots received 40 kg-N ha−1 for renovation and 190 kg-N ha−1 y−1 the following year. Carbon balance (i.e., the difference between C input through crop residue and C output through heterotrophic respiration), methane (CH4) and nitrous oxide (N2O) emissions, and herbage yield were measured over a period of 411 or 412 days. Cumulative N2O emissions were significantly smaller from F and S plots than from T plots, however, there was no significant difference in the sum of GHG emissions (i.e., C balance plus cumulative CH4 and N2O emissions) among F, S, and T plots. The cumulative total herbage yields of the F, S, and T plots did not differ significantly from each other. Consequently, the GHG intensity—i.e., the sum of GHG emissions per cumulative total herbage yield—was not significantly different among the F, S, and T plots.

Evaluation of morphological and production characteristics and nutritive value of 47 lucerne cultivars/lines in temperate Australia

ABSTRACTForty-seven lucerne varieties/lines were examined to quantify their morphological, production characteristics, and nutritive values in southeastern Australia. The experiment was established in 2015 with a randomized complete block design and four replications. The morphological and production characteristics were measured from January to October 2017, and nutritive values were measured in February 2017. The results showed that the cultivars differed significantly (P < 0.01) in morphological, production characteristics, and nutritive values. Total herbage yield was highest for Haymaster 7 (14,186 kg/ha) and lowest for Qingshui (5927 kg/ha). Plant height was highest for Cropper 9.5 (31.4 cm) and lowest for Qingshui (14.5 cm). SF 714QL had the greatest branch number (44.7 branches/15 cm row segment). AV1001 had longest leaf (2.3 cm) and greatest leaf area (16.68 cm2/10 leaves) whereas Force 10 and SARDI 10 SERIES 2 had widest leaves (1.3 cm). AV1005 had the highest leaf-to-stem ratio (5.64). Crude protein (CP) content was highest for SARDI 10 SERIES 2 (15.1%) and lowest for SF 714QL (8.0%). AV12 was highest in crude fat (4.5%). Neutral detergent fiber (NDF) content was lowest in Stamina 5 (33.5%). Acid detergent fiber (ADF) content was lowest in Gannong 4 (29.3%). Relative feed value (RFV) was highest in Force 11 (193.0%). Calcium (Ca) content was highest for Titan 5 (1.8%). Phosphorous content was highest for AV1 and Gannong 6 (0.1%). Overall, Cropper 9.5, SARDI 10 SERIES 2, Haymaster 9, Titan 9, SF 714QL, Kaituna, Haymaster 7, AV1001, AV1002, and WL925HQ performed well based on their comprehensive scores.

Influence of Melia dubia Cav. Spatial Geometries on Growth, Herbage Yield and Essential Oil Constituents of Cymbopogon martinii (Roxb.) Wats.

The present study was carried out to find suitable spatial geometry of Melia dubia (an industrially important fast growing tree) for Cymbopogon martinii by assessing its growth, physiology, herbage, and essential oil yield and major essential oil constituents. Sole cropping (C. martinii) and silvi-medicinal systems viz., M. dubia (2x2 m)+C. martinii, M. dubia (3x3 m)+C. martinii, M. dubia (3x2 m)+C. martinii, M. dubia (4x4 m)+C. martinii and M. dubia (4x2 m)+C. martinii resulted significant (p ≤ 0.05) effect on growth, herbage yield, essential oil content and yield and major essential oil constituents of C. martinii. Height growth, number tillers, plant spread and physiological parameters were better under M. dubia (2X2 m)-C. martinii silvi-medicinal system. Total fresh, dry herbage and essential yield was higher under M. dubia (2X2 m)-C. martinii system compared to wider spatial geometries and sole cropping. Oil yield was higher under silvi-medicinal systems compared to sole cropping system. The essential oil recovery was also higher under M. dubia compared to sole cropping of C. mrtinii. Growth and yield attributes were higher at 2nd harvest compared to 1st and 3rd harvest. Geranyl acetate percentage was higher under closer spacing of M. dubia and it was less in sole crop. However, geraniol content was higher in sole crop and wider spatial geometries of M. dubia.

Direct recovery of 33 P-labelled fertiliser phosphorus in subterranean clover ( Trifolium subterraneum ) pastures under field conditions – The role of agronomic management

Abstract Grazing systems are a major producer of food and fibre across the world. These systems often require the addition of fertiliser phosphorus (P) for maximum pasture growth, and it is now estimated that a four-fold increase in the use of P fertiliser in grasslands is needed to meet increased food demand by the year 2050. However, the recovery of P from fertiliser is often inefficient and global issues associated with P scarcity will continue to worsen. Knowledge on the uptake of fertiliser P by grasslands, including the effect of agronomic management, remains incomplete under field conditions. The aim of this study was to quantify the effects of soil P fertility (across three levels of soil P fertility), time of fertiliser application (at one level of soil P fertility), and placement of fertiliser (at one level of soil P fertility) on the growth and uptake of fertiliser P by clover pastures during a growing season. Subterranean clover (Trifolium subterraneum L.) monocultures established at two field sites in Australia were used to test the growth response to, and recovery of: (i) early-season (autumn) additions of fertiliser P to the soil surface at three levels of soil P fertility; (ii) mid-season (late winter) additions of fertiliser P to the soil surface; and (iii) early-season additions of fertiliser P placed 6 cm below the soil surface. Fertiliser P was applied to the pastures as single superphosphate that was labelled with a 33P radiotracer to supply ∼20 kg P ha−1. Total herbage yield and recovery of fertiliser P by the clover pastures was generally highest when fertiliser P was applied to the soil surface early in the growing season and to soils maintained at the optimum level of soil P fertility for maximum pasture growth. An audit of the 33P recovery of fertiliser P in the clover pasture revealed that up to 50% of the fertiliser P was recovered by the clover plant (shoots and roots), 5–15% remained in the fertiliser granule, and 20–25% was recovered in the 0–4 cm soil layer (largely as inorganic P) by the end of the growing season. We demonstrate that clover pastures are able to recover a relatively large proportion of surface applied fertiliser P during a growing season. Surface application is the simplest and most cost-effective strategy for management of fertiliser P in pastures.

Evidence for Heterosis in Italian Ryegrass (Lolium multiflorum Lam.) Based on Inbreeding Depression in F2 Generation Offspring from Biparental Crosses

Italian ryegrass is one of the most important temperate forage grasses on a global basis. Improvement of both dry matter yield and quality of herbage have been major objectives of pasture grass breeding over the last century. F1 and F2 progeny sets derived from controlled pair-crosses between selected Italian ryegrass genotypes have been evaluated for yield and nutritive quality under field conditions. Linear regression of the performance of F1 families under sward conditions on parental genotype means in a spaced plant trial was significant for quality characteristics, but not for herbage yield. This result suggests that phenotypic selection of individual plants from spaced plant nursery is feasible for improvement of nutritive quality traits, but not for yield. The presence of significant heterosis within F1 populations was demonstrated by reduced herbage production in subsequent F2 populations (generated by one cycle of full-sib mating), an up to 22.1% total herbage yield in fresh weight, and a 30.5% survival rate at the end of the second reproductive cycle. Potential optimal crosses for exploiting such heterosis are discussed, based on construction and the inter-mating of complementary parental pools, for the implementation of a novel F1 hybrid production strategy.

Strategic timing of nitrogen fertilization to increase root biomass and nitrogen-use efficiency of Lolium perenne L.

Aims: During the first days after harvest of Lolium perenne L., N remobilized from roots and stubble forms the main N source for regrowth. Low N uptake from the soil during this period may lead to N loss if N fertilizer is applied too soon. Furthermore, temporary N deprivation has been found to stimulate root growth. We therefore hypothesized that a strategic delay in N application after harvest may improve N-use efficiency of L. perenne grassland by increasing root biomass and reducing N loss. Methods: In a laboratory and field experiment with L. perenne, we delayed N fertilizer application after harvest for 0, 3, 6, 9 and 12 days, repeated this for up to six harvest cycles, and determined effects on herbage yield, herbage N uptake and root biomass. Results: In both experiments, delaying N application for up to 12 days had no significant effect on root biomass or total herbage N uptake, but it significantly reduced total herbage yield in the laboratory experiment. Total yield tended to be highest when N application was delayed for 3 days. Two growth periods in the field experiment showed significantly higher N uptake when N application was delayed, possibly due to rainfall-induced N losses in the treatments with shorter delay. Conclusions: Our results do not provide evidence that delaying N application improves N-use efficiency of L. perenne grassland by increasing root biomass. However, strategic timing of N fertilizer application based on rainfall forecasts could contribute to improve N-use efficiency by reducing N losses from leaching and denitrification.

Production improvement through phosphorus fertilization and legume introduction in grazed native pastures of Uruguay

SUMMARYThe objective of the current study was to quantify the response of pasture to phosphorus (P) fertilizer application and legume introduction, by measuring herbage yield, nitrogen (N) and P content, and weight gain of calves in native pastures of Uruguay. Quantitative relationships between pasture characteristics and post-weaning daily live weight gain (DLWG) were also examined. The treatments studied were native grassland (NG) and improved pasture, oversown withLotus corniculatusL. andTrifolium repensL. with annual applications of either 13 and 26 kg P/ha. From 1996 to 2001 the treatments were evaluated each year with a new group of calves. Total herbage yields of the oversown pastures were not always higher than NG in the initial years, but legume production increased, although without significant differences between P rates on legume or total yield. This was also reflected in the N and P status of the swards. In the last 2 years legume proportion had declined to &lt;0·1, but total herbage yield was significantly higher in the improved pastures. The average DLWG over the 6 years of measurements were 0·319, 0·478 and 0·586 kg/day for NG, P1 and P2, respectively, with average total live weight gain increased 1·8- and 2·5-fold by the legume introduction and annual addition of 13 and 26 kg P/ha, respectively. The study demonstrated that the evaluation of pasture response to P application should not be limited to assessing forage yield increase. Phosphorus availability in the herbage was a better predictor of animal performance than pasture yield. The study highlights that the benefits of oversowing and fertilizer inputs are short-lived, as withholding of fertilizer in the last 2 years resulted in a loss of sown legumes and decline in animal production.

Seasonal development of biomass yield in grass–legume mixtures on different soils and development of above- and belowground organs of Medicago sativa

Grass–legume mixtures are suitable for crop rotations under organic farming. Little attention has been paid to seasonal development of mixtures with alfalfa under field conditions. We investigated the effects of site and cut on herbage and belowground biomass yields of grass–legume mixture and on above- and belowground traits of Medicago sativa. Six sites in southern Germany were monitored during 2011. Dry matter herbage yield ranged from 9 to 16 t ha−1. The total herbage yield of three cuts per year decreased from 45% to 36% and 19%. The belowground biomass in the upper 30 cm soil layer ranged from 1.7 to 3.8 t ha−1.There was no seasonal trend. Diameter of the root neck and maximum order of branching of alfalfa increased during the season. The number of nodules per plant decreased from 9.5–17.0 in May to 7.5–13.0 in August. By the last cut, roots with larger diameter created smaller nodules. More branched roots created more nodules independent of their shape. Thinner roots have more active nodules. Plant height, number of stems and inflorescences per plant were higher in July and August than in May. In conclusion, a holistic analysis including above- and belowground traits should be used for the evaluation of fodder crops.

Effects of Seed Proportion and Planting Pattern on Dry Matter Yield, Compatibility and Nutritive Value of &lt;i&gt;Panicum coloratum&lt;/i&gt; and &lt;i&gt;Stylosanthes guianensis&lt;/i&gt; Mixtures under Bako Condition, Western Oromia, Ethiopia

Panicum coloratum (PC) and Stylosanthes guianensis (SG) mixed pasture was established to assess the effect of seed proportion and planting pattern on Dry Matter Yield (DMY), compatibility and nutrient content of the mixed stand. Seeds of PC and SG were mixed as 50%PC+50% SG and 25% PC+75% SG and sown in same row, alternate row and broad casting pattern. A randomized complete block design with four replications was used to layout the experiment. The 50%PC+50%SG proportion resulted in significantly (p&lt;0.01) higher DMY for PC (p&lt;0.0001) while the 75% SG+25%PC mixture resulted in significantly higher DMY of SG (p&lt;0.0001). For PC and SG, and total herbage yield, an alternate row planting pattern gave significantly highest (p&lt;0.0001) yield, followed by broadcasting. Planting along the same row resulted in inferior values (p&lt;0.0001) for all parameters, which perhaps is induced by the severity of competition between species. The RY (Relative Yield), LER (Land Equivalent Ratio),and CR (Competitive Ratio) values also imply similar trends for DMY of the component species. The legume DMY steadily increased from first to third year for the 75% SG+25% PC proportion. It can thus be concluded that the 50%PC+50SG proportion sown in alternate pattern was favorable for DMY in PC whereas the 25%PC+ 75%SG proportion combined with alternate rowpattern was appropriate for the legume. Intercropping SG into PC sward at 25%PC+75%SG mixed proportions also improved the CP content, IVDMD and reduced NDF content.

Components of herbage accumulation in elephant grass cvar Napier subjected to strategies of intermittent stocking management

SUMMARYHerbage accumulation is determined by the tissue turnover of individual plants and by the regulation patterns of the number of individuals in a plant population, which function in conjunction to enable swards to adapt to variations in growth and management conditions. Based on the hypothesis that intermittent grazing strategies change the proportion of basal and aerial tillers and, consequently, sward herbage accumulation, the objective of the current experiment was to evaluate the components of herbage accumulation in elephant grass cvar Napier (Pennisetum purpureum Schum. cvar Napier) from January 2011 to April 2012. The treatments corresponded to combinations of two post-grazing (post-grazing heights of 35 and 45 cm) and two pre-grazing conditions (0·95 and maximum canopy light interception during regrowth – LI0·95 and LIMax) and were allocated to experimental units (850 m2 paddocks) according to a 2×2 factorial arrangement in a complete randomized block design with four replications. The following response variables were evaluated: the population density of basal tillers (TPDb) and the population density of aerial tillers (TPDa), the number of aerial tillers per supporting unit (A/B+VC), growth rates of the leaf (LGR) and stem (SGR), leaf senescence rate, net leaf accumulation rate (LAR), and the contributions of basal and aerial tillers to sward growth and senescence. The swards managed with the LI0·95 target had greater TPDb than those managed with the LIMax target, but no difference was recorded between the LI pre-grazing targets for TPDa. The larger A/B+VC ratio recorded for the swards managed with the LIMax target resulted in a higher contribution of aerial tillers to the growth and senescence of swards. This growth strategy resulted in a higher SGR and lower LGR and LAR for the swards managed with the LIMax target relative to those managed with the LI0·95 target. The post-grazing height targets affected only LGR during winter and the second summer and SGR on average for the experiment, with higher values recorded for the swards managed at 35 cm. The LI pre-grazing targets played a central role in defining the compensatory mechanisms responsible for the competitive ability of the plants, which were primarily expressed in the variation of the proportion of basal and aerial tillers in the tiller population and interfered with the components of herbage accumulation and total herbage yield of the swards.

Simple quantitative method for estimation of herbage damage caused by sika deer (Cervus nippon)

AbstractQuantitatively estimating herbage damage caused by wild herbivores, such as deer, provides a basis for developing countermeasures designed to prevent the damage. However, a simple and easy way to quantify deer damage has not yet been developed. In this study, we estimated herbage damage caused by sika deer (Cervus nippon) in three meadows of a dairy farm in central Japan during three cutting periods. We then compared the validity of quantitative estimation of herbage damage using three simple methods: by comparing plant height or plant length outside and inside a deer exclosure cage, and by estimating the density of sika deer populations using spotlight census surveys in the meadows. We also examined the effect of the timing of herbage damage (i.e. early, middle and late season) caused by sika deer on a total herbage yield during each cutting period. The decreased plant height outside of a deer exclosure had a significant and unbiased linear relationship with herbage damage caused by sika deer. However, the decreased plant length outside of a deer exclosure had a significant but biased linear relationship with herbage damage caused by sika deer. The required sample size for assessing the difference in plant height outside of a deer exclosure increased when the herbage damage was small. On the other hand, the mean density of sika deer did not have a linear relationship with herbage damage. The timing of herbage damage caused by sika deer did not significantly affect total herbage yield. These results show comparing plant height outside and within a deer exclosure provides a simple and inexpensive quantitative method that can be used to estimate herbage damage caused by sika deer. This simple method, however, can be reliable when the herbage damage is relatively large (e.g. &gt;30%).

The effects of simulated summer‐to‐winter grazing management on herbage production in a grass–clover sward

AbstractThe effects of summer‐to‐winter simulated grazing management factors, namely defoliation interval (INT: 21, 42, 56 or 84 d), defoliation height (DH: 2·7, 3·6, 5·3 or 6·0 cm) and final defoliation date (FIN: 23 September, 4 November or 16 December) on herbage production in a grass–clover sward were studied. Treatments were imposed between July and December 2008, with all plots under common management in the following March to June 2009. The 42‐d INT achieved the highest (P &lt; 0·001) total herbage yield at 11·00 t DM ha−1. Shorter (21 d) and longer (56–84 d) intervals reduced annual clover herbage yield and biological nitrogen fixation estimates. Lowering DH from 6·0 to 2·7 cm in the summer‐to‐winter period increased sward clover content and clover herbage yield through to the following June, 6 months after treatments ended. Delaying FIN from 23 September to 16 December had no significant effect on annual clover, grass or total herbage yield. Spring–summer clover herbage yield was positively correlated with spring–summer clover stolon mass (R2 = 0·54, P &lt; 0·001) and, to a lesser extent, light penetration through the sward in the previous winter (R2 = 0·16, P &lt; 0·05). A 42‐d INT with low DH (2·7–3·5 cm) is therefore recommended for grass–clover swards.

Effect of tree plantation on composition, standing biomass and diversity of ground vegetation on sodic land of North-East region of Uttar Pradesh

The structure,composition, yield and diversity of ground vegetation under eight tree plantations on sodic wasteland were compared among each other and with an adjacent open stand. The communities were floristically distinct from each other on different stands. However, the community on open stand was relatively more similar with the communities under Eucalyptus tereticornis and Acacia catechu plantation stands than with other stands. The herbage yield was lowest on open stand and it was higher under Acacia auriculiformis and Casuarina equisetifolia plantation stands. The contribution of grasses to the total herbage yield was maximum (98%) on open stand and minimum (27%) under C. equisetifolia plantation stand. Herbage yield in the present study also indicated an inverse relationship with soil ESP and pH, thus suggesting that on improving the sodic level of the soil, the herbage yield also increased. Shannon – Wiener diversity was lower, while concentration of dominance was higher for ground vegetation on open stand than any of the plantation stand. Among the plantation stands, diversity was higher under A. catechu, E. tereticornis and Terminalia arjuna plantation stands than under other plantation stands. Diversity tended to show a positive relation with the herbage yield, whereas the relationships between diversity and soil ESP and pH were negative. Dominance-diversity curves for all the herbaceous communities fit the geometric series. Single species dominance is more pronounced in the community on open stand than the communities under tree plantation stands.

The Effects of Glyphosate‐Tolerant Technology on Reduced Alfalfa Seeding Rates

Higher costs associated with glyphosate tolerant (GT) compared to nonGT alfalfa (Medicago sativa L.) seed stimulates questions about reduced seeding rates in combination with the GT technology. Our objective was to determine if glyphosate herbicide in combination with GT alfalfa could improve the persistence, productivity, or forage quality when seeding alfalfa at a reduced rate. Glyphosate‐tolerant alfalfa was seeded at seven locations into conventionally tilled seedbeds at rates of 6.7, 11.2, 15.7, and 20.2 kg ha−1 pure live seed (PLS) in the spring of 2006. Stand density, botanical composition, yield, and forage quality were determined for each seeding rate under three herbicide treatments: (i) glyphosate [N‐(phosphonomethyl)glycine], (ii) a nonglyphosate herbicide, and (iii) no herbicide. Level of weed infestation was different among locations, but there were no weed infestation × seeding rate or herbicide × seeding rate interaction. Lower seeding rates had lower plant mortality than higher seeding rates. Seeding rate had no affect on forage quality or weed content at any harvest. At only the first harvest in the seeding year did the 6.7 kg ha−1 seeding rate produce less alfalfa forage (about 250 kg ha−1) than other seeding rates. In both the seeding year and year after seeding, using herbicides resulted in less weed and greater alfalfa yield than when no herbicide was used. Regardless of weed control treatment, seeding rates of GT alfalfa greater than 6.7 kg ha−1 did not improve weed control, alfalfa yield, total herbage (alfalfa + weeds) yield, or forage quality.