Highest Total Dry Matter Yield Research Articles

Effects of Maize Varieties on Biomass Yield and Silage Quality of Maize–Soybean Intercropping in the Qinghai–Tibet Plateau

Forage deficiency is the bottleneck that restricts the development of plateau animal husbandry. Maize (Zea mays L.)–soybean (Glycine max L.) intercropping can improve the forage biomass yield and silage quality. This experiment was conducted in Ganzi Tibetan Autonomous Prefecture to explore the effects of four maize varieties (M1, Rongyu Silage No. 1; M2, Yayu 04889; M3, Demeiya No. 1; M4, Zhenghong 505) on biomass yield, nutritional composition, and silage quality in maize–soybean intercropping. The results showed that M1S had the highest total dry matter yield (18.03 t ha−1), M3S had the highest crude protein (CP) content (8.46% DM), and soybeans had the highest water-soluble carbohydrate (WSC) content (8.55% DM). After silage, the CP content (13.44% DM) of mixed silage in M3S was higher, and the contents of neutral detergent fiber (39.42% DM) and acid detergent fiber (25.42% DM) were lower than those in maize silage alone. The WSC content (4.45% DM) of mixed silage in M3S was higher and the pH value (4.46) and ammonia–nitrogen to total nitrogen (3.97%) were lower than those of soybean silage alone. The results of membership function analysis showed that M3S was the best in fresh feeding and silage utilization, followed by M1S. Therefore, M3S (Demeiya No 1. intercropped with soybeans) is recommended in high-altitude areas.

Yield and nutritional value of Moringa oleifera forage at different population densities

Objective: To evaluate the aerial biomass yield and nutritional value of Moringa oleifera at densities of 50,000 (D1), 100,000 (D2) and 200,000 (D3) plants ha-1. Design/methodology/approach: The experiment was established under a random complete block design arranged in divided plots and three repetitions and from 155 days after planting 5 cuts were made every 28 days. The variables evaluated were yield (kg ha-1) of total dry matter (TDM), sheet (sDM) and contents (g kg-1) of crude protein (CP), neutral detergent fiber (NDF) and acid (ADF).
 Results: An interaction between densities and cuts was observed. In TDM performance, in cuts 1 and 2, D1 outperformed D2 and D3, by 71 % and 83 %, respectively; however, D3 had the highest TDM yield (P<0.05) in cuts 3 and 4, 47 % higher than D2 and D1 and D2 by 46 % and 76 %, respectively. The highest yield of sDM was presented in D1, in cuts 1 and 2 (561 and 852 kg ha-1, respectively); while D3 showed the highest values in cuts 3 and 4, (901 and 1054 kg ha-1, respectively). When increasing from D1 to D2 there was a decrease (P<0.05) in the CP content of 11 % (222 vs. 198 g kg-1). Regarding the values of NDF and ADF, no differences (P>0.05) were found between the densities evaluated.
 Limitations/implications: The density of plants in Moringa oleifera determine the yield potential and nutritional value of the forage.
 Findings/conclusions: Moringa oleifera established in semi-arid conditions at a density of 50,000 ha-1 plants and with cutting intervals of 28 days, presented the best productive behavior in terms of yield and protein concentration.

Alfalfa-grass mixtures reduce greenhouse gas emissions and net global warming potential while maintaining yield advantages over monocultures

Improving forage productivity with lower greenhouse gas (GHG) emissions from limited grassland has been a hotspot of interest in global agricultural production. In this study, we analyzed the effects of grasses (tall fescue, smooth bromegrass), legume (alfalfa), and alfalfa-grass (alfalfa + smooth bromegrass and alfalfa + tall fescue) mixtures on GHG emissions, net global warming potential (Net GWP), yield-based greenhouse gas intensity (GHGI), soil chemical properties and forage productivity in cultivated grassland in northwest China during 2020–2021. Our results demonstrated that alfalfa-grass mixtures significantly improved forage productivity. The highest total dry matter yield (DMY) during 2020 and 2021 was obtained from alfalfa-tall fescue (11,311 and 13,338 kg ha−1) and alfalfa-smooth bromegrass mixtures (10,781 and 12,467 kg ha−1). The annual cumulative GHG emissions from mixtures were lower than alfalfa monoculture. Alfalfa-grass mixtures significantly reduced GHGI compared with the grass or alfalfa monocultures. Furthermore, results indicated that grass, alfalfa and alfalfa-grass mixtures differentially affected soil chemical properties. Lower soil pH and C/N ratio were recorded in alfalfa monoculture. Alfalfa and mixtures increased soil organic carbon (SOC) and soil total nitrogen (STN) contents. Importantly, alfalfa-grass mixtures are necessary for improving forage productivity and mitigating the GHG emissions in this region. In conclusion, the alfalfa-tall fescue mixture lowered net GWP and GHGI in cultivated grassland while maintaining high forage productivity. These advanced agricultural practices could contribute to the development of climate-sustainable grassland production in China.

SOWING ARRANGEMENTS OF SORGHUM WITH BRACHIARIA FOR FORAGE PRODUCTION AND SOIL COVER

The objective of this study was to evaluate the dry matter production and morphological parameters of sorghum and brachiaria (signalgrass, specifically palisade grass) grown simultaneously for forage production, along with the formation of soil cover in the off-season. The treatments were in a randomized block design and consisted of three different sowing arrangements: sorghum + two rows of brachiaria (between sorghum rows), sorghum + two rows of brachiaria (one in the row + another between the sorghum rows), and sorghum with brachiaria broadcast; as well as sorghum and brachiaria grown in monoculture. The dry matter yield of sorghum in the 1st cycle was higher in the arrangement of sorghum alone, obtaining around 12.01 t ha -1 . The highest total dry matter yield was obtained in the arrangement of sorghum with broadcast brachiaria, with 11.01 t ha -1 for sorghum and 3.75 t ha ‑1 for the brachiaria. In the 2nd cycle, soil cover was greatest in the brachiaria monoculture and in the arrangement of sorghum with broadcast brachiaria, at 95% and 86%, respectively. With the aim of producing forage sorghum together with the formation of adequate soil cover by brachiaria, the arrangement of sorghum with broadcast brachiaria is promising.

Agronomic and chemical evaluation of hop cultivars grown under Mediterranean conditions

Aim of study: Evaluation of the agronomic performance and chemical profile of four hop cultivars grown under Mediterranean conditions.Area of study: The study was undertaken in Bragança, north-eastern Portugal.Material and methods: The newly introduced cultivars (‘Columbus’, ‘Cascade’ and ‘Comet’) were compared with the well-stablished ‘Nugget’. The field experiment was carried out between 2017 and 2019. Dry matter (DM) yield (plant and cones), tissue elemental composition and bitter acid and nitrate (NO3-) concentrations in the cones were assessed.Main results: ‘Comet’ was the most productive cultivar with the highest total DM yield (1,624 to 1,634 g plant-1), cone yield (572 to 633 g plant-1), and dry weight of individual cones (0.28 to 0.79 g cone-1). ‘Cascade’ showed the lowest average total DM yield (723 to 1,045 g plant-1). The year affected the average values of DM yield and the concentration of bitter acids in the cones, with ‘Cascade’ showing the highest sensitivity between cultivars. The concentrations of α and β-acids in the cones were within or close to the normal ranges internationally accepted for all cultivars. ‘Columbus’ exhibited the highest levels of α-acids, ranging between 12.04 % and 12.23%, followed by ‘Nugget’ (10.17–11.90%), ‘Comet’ (9.32–10.69%) and ‘Cascade’ (4.46–8.72%). The nutrient accumulation criteria in cone and leaf tissues seem to be a differentiating factor between cultivars with influence on bitter acid biosynthesis and biomass production.Research highlights: All cultivars showed notable performance in terms of DM yield and bitter acid concentration in the cones when compared to international standards.

CO2 exchange, dry matter accumulation and growth response of sorghum (Sorghum bicolor L. Moench) to terminal drought as affected by potassium and blended‐NPSBZn fertilization

AbstractSorghum production is constrained by terminal drought stress in semi‐arid areas of north‐eastern Ethiopia. Data from field experiments conducted in the region for two consecutive years (2015 – 2016) were used to investigate the effect of potassium (K) and NPSBZn‐blended fertilizer (BF) inputs on the drought response of sorghum through analysis of gas exchange, dry matter accumulation and growth parameters. Leaf gas exchange properties varied strongly with K and BF application both under normal rainfall and drought conditions. Data taken at anthesis in drought‐exposed sorghum indicated reduction of net photosynthetic rate (AN) with BF supply. AN declined from 15.7 µmol CO2/m2/s in the control to 13.4 µmol CO2/m2/s with application of 164 kg/ha BF. However, higher total dry matter yield was recorded at maturity in response to blended fertilizer and K inputs. Increasing supply of NPSBZn‐blended fertilizer was associated with declining leaf K content, increasing intercellular CO2 concentration and water use efficiency (WUE) during anthesis. Significant variations in crop growth rates were also observed in response to K and BF inputs. At physiological maturity, net assimilation rate (NAR) increased with K and BF inputs both under drought and normal rainfall conditions. In general, K application modulated the response of sorghum to BF input under both normal rainfall and drought conditions. Therefore, grain sorghum could benefit from early supply of K and BF fertilizer in drought prone areas of Northeastern Ethiopia.

Evaluation of <i>Vicia</i> Species and Their Accessions for Forage Biomass Yield in Benishangul-Gumuz Region of Western Ethiopia

A study was carried out to evaluate four <i>Vicia</i> accessions from 3 species for forage biomass yield performance under two environmental conditions of the Benishangul-Gumuz Region of Western Ethiopia. The evaluated <i>Vicia</i> species and accessions were one <i>V. benghanlensis</i> (6798), two <i>V. villosa </i>(6213 and 6792) and one <i>V. sativa</i>, (5172) accessions. The experiment was conducted at Tongo and Assosa forage research station of Assosa Agricultural Research Center and the locations were purposively selected to represent highland and mid-altitude agro-ecologies, respectively. The experiment was set up with a randomized complete block design with three replications. Main effects differences among genotypes and environments significantly influenced forage dry matter yield (P < 0.05) and plant height (P < 0.01), while the leaf to stem ratio was significantly (P < 0.001) influenced by the environment. Tongo had the highest forage dry matter yield (P < 0.01) compared to Assosa. Plant height was significantly different among accessions at both locations and the tallest plant height at forage harvest was recorded for <i>V. villosa </i>6213 followed by <i>V. benghanlensis</i> 6798 and <i>V. villosa </i>6792 at both locations. At Tongo, total dry matter yield was significantly different (P < 0.05) among accessions, but not at Assosa (P > 0.05). <i>V. benghanlensis</i> 6798 gave a relatively higher total dry matter yield followed by <i>V. villosa </i>6792 and <i>V. villosa </i>6213 at Tongo. Therefore, based on forage dry matter yield data <i>V. benghanlensis</i> 6798, <i>V. villosa </i>6792 and <i>V. villosa </i>6213 recommend as alternative legume forage crops from evaluated <i>Vicia</i> accessions for study areas and comparable agro-ecologies.

Intercropping irrigated corn with two soybean maturity groups at different planting rates for forage

AbstractIncreasing silage production and quality is paramount for dairy and beef feedlot production. We aimed to (a) increase dry matter, protein production, and profit per acre of corn (Zea mays L.) by intercropping it with soybean [Glycine max (L.) Merr.]; (b) compare soybean maturity groups (MGs) intercropped or grown as the sole crop; and (c) quantify the soybean planting rate's influence on land equivalent ratios (LER), total dry matter yield, nutrient concentration and economic return per acre in corn–soybean intercropping systems. A 2‐yr field study was conducted with two soybean MGs (MG1 and MG7) and four soybean planting rates: 0 (control), 38,000 (1×), 76,000 (2×), and 152,000 (4×) seeds acre−1. Intercropping with MG7 increased soybean dry weight by 33% compared with MG1. The MG7 4× rate in 2012 and the 1× and 2× rates in 2013 maximized yield and LER when forage contained 7 to 10% soybean. Averaged over years, the MG7 soybean planting rate had a significant quadratic influence on nutrient value, peaking at the 2× rate at $23 ton–1 more than monoculture corn. Intercropping with the 2× MG7 soybean increased the net economic return per acre on a nutrient value basis by $238 acre−1. The soybean concentration in the mix that produced the highest total dry matter yield 5 and 7% and 7 and 10% for gross economic return per acre in 2012 and 2013, respectively. On a tonnage only basis, intercropping 2× MG7 soybean increased yield and produced $26 acre−1 more profit than monoculture corn.

Do agricultural grasses bred for improved root systems provide resilience to machinery-derived soil compaction?

The increasing frequency of droughts and floods on grasslands, due to climate change, increases the risk of soil compaction. Soil compaction affects both soil and forage productivity. Differing grasses may counteract some effects of compaction due to differences in their root architecture and ontogeny. To compare their resilience to soil compaction, three Festulolium (ryegrass and fescue species’ hybrids) forage grass cultivars comprising differing root architecture and ontogeny were compared in replicated field plots, together with a ryegrass and tall fescue variety as controls. Pre‐compaction soil and forage properties were determined in spring using > four‐year‐old plots to generate baseline data. Half of each field plot was then artificially compacted using farm machinery. Forage dry matter yield (DMY) was determined over four cuts. After the final harvest, post compaction soil characteristics and root biomass (RB) were compared between grasses in the non‐compacted and compacted soils. Pre‐compaction data showed that soil under Festulolium and ryegrass had similar water infiltration rates, higher than soil under tall fescue plots. Tiller density of the Festulolium at this time was significantly higher than fescue but not the ryegrass control. Forage DMY was significantly lower (p < .001) with compacted soil at the first cut but, by the completion of the growing season, there was no effect of soil compaction on total DMY. Tall fescue had a higher total DMY than other grasses, which all produced similar annual yields. Soil bulk density and penetration resistance were higher, and grass tiller density was lower in compacted soils. Root biomass in compacted soils showed a tendency for Festulolium cv Lp × Fg to have higher RB than the ryegrass at 0–15 cm depth. Overall, findings showed alternative grass root structures provide differing resilience to machinery compaction, and root biomass production can be encouraged without negative impacts on forage productivity.

Effect of rice straw biochar and irrigation on growth, dry matter yield and radiation‐use efficiency of maize grown on an Acrisol in Ghana

AbstractIn order to determine whether the current low productivity associated with rainfed cultivation on degraded soils in Ghana can be improved by biochar amendment and irrigation, field experiments with maize were conducted over two seasons in 2017 and 2018. Rice straw biochar at rates of 0 t/ha (B0), 15 t/ha (B15) and 30 t/ha (B30) was combined with irrigation regimes of full irrigation (I100), deficit irrigation (I60) and no irrigation (I0). The I100 treatment was irrigated to field capacity every 3–4 days according to time domain reflectometry measurements while the I60 treatment received 60% of the irrigation amount given to I100 but with the same irrigation frequency. The I0 treatment was not irrigated. In both seasons, the B30 treatment recorded the highest total dry matter yield (TDMY), intercepted photosynthetically active radiation (IPAR) and radiation‐use efficiency (RUE) and these were significantly (p ≤ .05) higher than B0 except for RUE in 2017. Irrigation regimes did not significantly affect TDMY, IPAR and RUE in 2017 but compared to I100, I0 significantly reduced TDMY, IPAR and RUE in the relatively dryer 2018 season. Measured ratio vegetation indices differentiated biochar treatments earlier in the 2018 season than during 2017 and increase of leaf chlorophyll content indices with biochar rate in both seasons indicated that biochar amendment improved nitrogen uptake. Our study demonstrated that rice straw biochar is capable of increasing TDMY, IPAR and RUE of maize grown on degraded soils in Ghana. The study further showed that TDMY, IPAR and RUE of deficit irrigated maize for two seasons were similar to the counterpart fully irrigated maize and may be a viable water management option for farmers in Ghana to save irrigation water resources.

Effect of different spacing of Napier grass (Pennisetum purpureum) intercropped with or without Lablab (Lablab purpureus) on biomass yield and nutritional value of Napier grass

This study was conducted with an objective of determining effect of three spacing of Napier grass intercropped with or without Lablab (Lablab purpureus) on the biomass yield and nutritive value of Napier grass forage in a 2 x 3 factorial arrangement in RCBD with 4 blocks. Spacing was 1m x 0.5m, 0.75m x 0.5m, and 0.5m x 0.5m. Intercropping decreased the electro conductivity but increased the available phosphorous content of the soil and did not affect the pH, organic carbon and total nitrogen of the soil. Spacing, intercropping and their interaction had no significant effect (P>0.05) on dry matter (DM) yield (DMY) and crude protein (CP) yield (CPY) of the Napier grass. Intercropping and interaction of intercropping with spacing resulted to higher total DMY and CPY (P<0.05). The chemical composition of Napier grass was unaffected by spacing and interaction of intercropping with spacing. Intercropping of Napier grass with lablab however, increased the DM contents (P<0.05) of the Napier grass and decreased the ash contents. In conclusion, intercropping with lablab had a positive influence on the TDMY, TCPY, DM, hence increase the total forage yield and nutritive value of Napier grass. Conversely, spacing failed to have significant impact on these parameters. As such 1 m x 0.5m spacing and intercropping with lablab can be of a better choice based on the results of this study.

Investigation of feed value of alfalfa (Medicago sativa L.) harvested at different maturity stages

The aim of this study was to determine the green herbage and dry herbage yield, chemical and nutritional values and RFV of alfalfa (Medicago sativa L.) at different stages of maturity under Isparta ecological conditions in 2012. To achieve this goal random sampling plots was created according to an experimentation pattern, and the number of harvests was determined according to regional conditions. In chemical analysis, the following samples were analyzed for Dry Matter (DM), Crude Protein (CP), Ether Extract (EE), Ash, Crude Fiber (CF), Nitrogen Free Extract (NFE), Notral Detergent Fiber (NDF) and Acid Detergent Fiber (ADF), as well as macro and micro minerals. The highest total green herbage yield was 9609.33 kg/da during the budding period, which decreased by 28% with maturity. The highest total dry matter yield, which depends on hay yield, was determined as 1742.63 kg/da at the beginning of the flowering period. The highest CP was determined during the budding period and decreased with maturity. DM, CS, NDF and ADF content increased while ash, Digestible Dry Matter (DDM), Total Digestible Nutrients (TDN), Dry Matter Intake (DMI), Metabolisable Energy (ME), Net Energy Lactation (NEL), and Digestible Energy (DE) content decreased with maturity. The highest RFV was determined during budding and the beginning of the flowering periods. Taking both yield and feed value results into consideration based on Isparta’s conditions, the best harvesting period of alfalfa was determined to be at the beginning of the flowering period.

Surfactant effect on forage yield and water use efficiency for berseem clover and basil in intercropping and limited irrigation treatments

Quantifying crop response to irrigation is important for establishing effective irrigation management strategies. The present study was conducted to evaluate the response of berseem clover and basil to limited irrigation in an additive intercropping system using a surfactant. The experimental treatments were carried out in split–split plots based on a completely randomized block design with three replications. The limited irrigation treatments comprised of replenishment of I100 full irrigation, I75=25% limited and I50=50% limited weekly evaporation and plant water requirements which were assigned to the main plots. The planting systems of sole berseem clover and sole basil culture along with additive inter cropping of berseem clover+50% basil were assigned to the subplots. Water treatments of control (water alone) and water+surfactant were assigned to the sub-subplots. Results show that severely limited irrigation (I50) dramatically reduced the forage yield of berseem clover and basil by 19.5% compared with the control (I100). The severity of the adverse effects of limited irrigation stress decreased by the surfactant application in irrigation by water+surfactant (9.5% decrement compared to full irrigation). The highest irrigation water use efficiency (2.7kgm−3) was achieved in I50 treatment with an added surfactant. The highest total dry matter yield (berseem clover+basil dry matter) (9257.9kgha−1) was obtained from additive intercropping of berseem clover 100%+basil 50% while irrigated by water+surfactant.

Yield Evaluation of Twenty-Eight Alfalfa Cultivars in Hebei Province of China

Cultivar selection is important for alfalfa (Medicago sativa L.) hay production. From 2009 to 2012, a field study was conducted to evaluate the dry matter yield (DMY) of 28 cultivars in Cangzhou District of Hebei province, China, and to determine the most suitable cultivars for this province and other zones with similar climate conditions. 28 alfalfa cultivars were sown in late March of 2009 and were harvested for hay four times in each subsequent year. The results showed that the climatic conditions resulted in significant differences in annual DMY among years, with the second year being the highest and the first year the lowest. The top five cultivars with the highest total DMY were L2750 (62.75 t ha−1), Horn (62.72 t ha−1), 86–266 (61.55 t ha−1), German (61.44 t ha−1) and Zhongmu 1 (61.18 t ha−1), respectively. Across all four years, first harvest had the highest ratios to annual DMY except the cultivar of Rambler, while the fourth harvest had the lowest ratio. There were positive correlation relationships between DMY of each harvest and annual DMY, and the correlation coefficients were all significant in four years. And the path coefficients of first harvest were always the highest in four years. The qualities showed small variations among these cultivars and the cultivar L3750 presented the highest crude protein in both years. Crude protein had significant positive correlation with relative feed value (RFV) in both years while crude fiber had significant negative correlation with RFV and crude fiber.

Yield of bolting winter beet (Beta vulgaris L.) as affected by plant density, genotype and environment

Winter beet roots and shoots might be a favorable substrate for biogas production in Central Europe. However, detailed information about the attainable yield of this crop is lacking. Thus, the impact of plant density, genotype and environmental conditions on total dry matter yield of winter beet crops that bolt after winter was investigated. A significant increase of the dry matter yield (esp. shoot) was expected by harvesting the 1st shoot after flowering in June followed by a final harvest of the whole plant in July. In 2009/10, 2010/11 and 2011/12, three series of field trials with (i) 3 target plant densities (148, 246, 370 thousand plants ha−1) and (ii) 3 different sugar beet genotypes were conducted at Göttingen (Lower Saxony, GER) and Kiel (Schleswig-Holstein, GER); (iii), additional field trials with 5 different sugar beet genotypes cultivated at 2 target plant densities (148, 246 thousand plants ha−1) were conducted in 2011/12, to investigate the relation between maximum taproot diameter and the shoot and taproot yield of bolting winter beet. The total dry matter yield considerably varied between 4 and 23tha−1. It was predominantly affected by the environment and to a substantially lower extent by plant density. Increasing plant densities increased the total dry matter yield, resulting in a significantly higher total dry matter yield at plant densities ≥300,000plantsha−1 compared with lower plant densities. Genotypic differences in total dry matter yield were negligibly small. Pruning in June substantially increased the total dry matter yield in July by ca. 8tha−1 only in one out of three environments.Final yield in June (without pruning) and July (pruning in June) was positively related with cumulated temperature and global radiation, but also with taproot dry matter yield before winter. The taproot, shoot (1st, 2nd) and total plant yield were positively correlated with maximum taproot diameter.In conclusion, high dry matter yields close to yields of established energy crops grown over winter were obtained with winter beet roots and shoots only under very favorable conditions (climate, single plant size). High yields can be achieved after good pre-winter development. However, for sufficient frost tolerance the taproot size of plants must be rather small. Hence, the cultivation of bolting winter beet under Central European climate conditions has to face a severe conflict of goals concerning winter survival and yield formation.

Biomass production and chemical composition of Moringa oleifera under different planting densities and levels of nitrogen fertilization

The effect of different planting densities (100,000 and 167,000 plants ha−1) and levels of nitrogen fertilization (0, 261, 521, and 782 kg N ha−1 year−1) on biomass production and chemical composition of Moringa oleifera was studied in a split-plot design with four randomized complete blocks over 2 years with eight cuts year−1 at the National Agrarian University farm in Managua, Nicaragua (12°09′30.65″N, 86°10′06.32″W, altitude 50 m above sea level). Density 167,000 plants ha−1 produced significantly higher total dry matter yield (TDMY) and fine fraction yield (FFDM), 21.2 and 19.2 ton ha−1 respectively, compared with 11.6 and 11 ton ha−1 for 100,000 plants ha−1. Growth rate in 167,000 plants ha−1 was higher than in 100,000 plants ha−1 (0.06 compared with 0.03 ton ha−1 day−1). Average plant height was 119 cm irrespective of planting density. Fertilization at the 521 and 782 kg N ha−1 year−1 levels produced the highest TDMY and FFDM in both years of the study and along all cuts. The interaction between cut and year was significant, with the highest TDMY and FFDM during the rainy season in the second year. Chemical composition of fractions showed no significant differences between planting densities. Significantly higher crude protein content was found in the coarse fraction at fertilizer levels 521 and 782 kg N ha−1 year−1 (87.9 and 93.7 g kg−1 DM) compared with lower levels. The results indicate that Moringa can maintain up to 27 ton ha−1 dry matter yield under dry tropical forest conditions over time at a planting density of 167,000 plants ha−1 if the soil is regularly supplied with N at a level of approximately 521 kg ha year−1 in conditions where phosphorus and potassium are not limiting.

Effects of Plant Spacing on Yields and Nutritive Values of Napier Grass (Pennisetum purpureum Schum.) Under Intensive Management of Nitrogen Fertilizer and Irrigation

There was a significant effect of plant spacing on total dry matter yield among 50 x 40, 50 x 40, 50 x 40 and 50 x 100 cm plant spacing of Napier Grass. The highest total dry matter yield of 70.84 t ha was -1 obtained from 50 x 40 planting configuration. There was significant effect of plant spacing on dry matter production of the grass from 8 harvests. In a 50 x 40 planting configuration, the range of dry matter production from 11 harvests was 2.6-10.19 t ha . Plant spacing did not have significant (p>0.05) effect on Crude Protein -1 (CP), Acid Detergent Fiber (ADF) and Dry Matter Digestibility (DMD) but Neutral Detergent Fiber (NDF) was significantly affected (p<0.01) by plant spacing. The ranges of CP, ADF, NDF and DMD under different planting configurations were 13.2-13.9, 41.5-43, 66.9-68.2 and 74.7-75.5%, respectively. Intensive management of Napier Grass pasture may help to overcome the problem of shortage and low quality of feed supply during the dry season.

Effects of time of first harvest, total amount of nitrogen, and nitrogen application method on total dry matter yield in twice harvesting of rice

We examined the effects of time of first harvest, total amount of nitrogen, and nitrogen application method on the total dry matter yield of a twice-harvested rice ( Oryza sativa L.) cultivar Taporuri grown in southwestern Japan. The highest total dry matter yield was 27.1 t ha −1. We examined the effects of two times of first harvest (booting stage versus full heading stage). Plants harvested at the full heading stage produced 50% higher dry matter yield of first crop than those harvested at the booting stage, because the plants had greater weights per tiller than those harvested at the booting stage. Plants harvested at the booting stage produced 37% higher dry matter yield of second crop than those harvested at the full heading stage, because the plants had greater dry weights per tiller than those harvested at the full heading stage. Overall, plants harvested at the full heading stage produced 8% higher total dry matter yield than those harvested at the booting stage. We also examined the effects of two total amounts of nitrogen (300 kg N ha −1 versus 150 kg N ha −1) and three nitrogen application methods (method 1: 33.3% applied at transplanting, 66.7% at the maximum tiller number stage, 0.0% at 7 days after the first harvest, and 0.0% at 21 days after the first harvest; method 2: 33.3, 33.3, 16.7, and 16.7%, respectively; method 3: 33.3, 0.0, 33.3%, and 33.3%, respectively). For the first crop, plants that received 300 kg N ha −1 produced 10% higher dry matter yield than those that received 150 kg N ha −1 in 2004. Plants that underwent nitrogen application methods 1 and 2 produced 21% and 23% higher dry matter yield of first crop than plants that underwent method 3, respectively. The increase in number of tillers per meter in the 300 kg N ha −1 treatment and in nitrogen application methods 1 and 2 resulted in the higher dry matter yields of first crop in these treatments. For the second crop, plants that received 300 kg N ha −1 produced 10% higher dry matter yield of second crop than those that received 150 kg N ha −1. Plants that underwent nitrogen application methods 2 and 3 produced 57% and 56% higher dry matter yield of second crop than method 1, respectively. The increase in number of tillers per meter in the 300 kg N ha −1 treatment and in nitrogen application methods 2 and 3 resulted in the higher dry matter yields of second crop in these treatments. Overall, plants that received 300 kg N ha −1 produced 7% higher dry matter yield than those that received 150 kg N ha −1 and plants that underwent nitrogen application method 2 produced 21% and 11% higher dry matter yield than those that underwent methods 1 and 3, respectively. Therefore, our findings suggest that to produce the highest total dry matter yield the best time for first harvest is the full heading stage and the best nitrogen management is to provide 300 kg N ha −1 in accordance with nitrogen application method 2.

Prospects of whole grain crops of wheat, rye and triticale under different fertilizer regimes for energy production

Abstract Cereal grain yield and biomass production are affected by fertilizer application strategies. In order to quantify the performance of wheat, rye and triticale cultivars for use as energy crops, field experiments with either modified phosphorus–potassium or potassium applications were designed at two locations in Denmark over a 3-year period. Five wheat cultivars (‘Astron’, ‘Herzog’, ‘Kosack’, ‘Kraka’ and ‘Ure’), two winter rye cultivars (the population cultivar ‘Motto’ and the hybrid cultivar ‘Marder’) and the triticale cultivar ‘Alamo’ were selected. The grain and straw fractions were analysed for biomass, ash and contents of nitrogen (N), K, Cl, sulphur (S) and Na. Dry matter yields varied between 11.5 and 15.9 t ha−1 at the two locations. Triticale and rye had a higher total dry matter yield than wheat, even at lower inputs of N fertilizer. Thus, the constant high yield of rye and triticale is an advantage for biomass for energy purposes. The mineral content of the grain fraction changed only little between years and locations. By contrast, large variations in the analysed ions in the straw fraction between years and locations were observed. The use of K fertilizers resulted in a significantly increased concentration of K in the straw. However, this increased concentration was eliminated in years with high precipitation in the final 3 weeks before harvest, where substantial amounts of K, Cl and S were removed. The results are discussed in relation to the possible use of grain crops for energy production.

Effects of twice harvesting on total dry matter yield of rice

We examined the effect of twice harvesting of forage rice with the first harvest at the full heading stage on total dry matter yield in the cultivars Taporuri, Mohretsu, and Hinohikari and in line Saikaishi 253 in southwestern Japan. Taporuri produced the highest total dry matter yield, with a value 60% higher than that of Hinohikari. The first crop of Taporuri had a longer duration of vegetative growth than those of Mohretsu and Hinohikari, and had the highest dry matter yield because of its greater weight per tiller than Hinohikari and its more tillers per square meter than Saikaishi 253, which had a similar duration of vegetative growth. The second crops of Mohretsu, Taporuri, and Saikaishi 253 had longer vegetative growth and higher dry matter yields than Hinohikari. Dry matter yields of both crops were closely related to the duration of vegetative growth and the weight per tiller, but not to tillers per square meter. These results suggest that cultivars with a long duration of vegetative growth, high weight per tiller, and adequate tillers per square meter can produce high dry matter yield in both crops. There was a significant interaction ( P < 0.05) in total dry matter yield between cultivar or line and cultivation type. The total dry matter yield of Taporuri in twice harvesting was about 10% higher than that in once harvesting, whereas that of Hinohikari was about 10% lower. The suitability for twice harvesting ([total dry matter yield in twice harvesting]/[total dry matter yield in once harvesting]) was significantly positively correlated ( r = 0.875) with the increase in dry weight before the full heading stage, but significantly negatively correlated ( r = −0.903) with the increase in dry weight between full heading and the yellow ripe stage. Thus, cultivars with a high increase in dry weight before full heading appear to be more suitable for twice harvesting than those with a high increase between full heading and the yellow ripe stage. In addition, our study showed that twice harvesting can prevent lodging in Taporuri, thereby increasing the suitability of this cultivar as a forage rice. Our results suggest that twice harvesting can be performed in southwestern Japan and warmer regions.