Narrow Row Research Articles

Design and Development of Mini Tractor Operated Multipurpose Equipment for Groundnut Crop

A study was developed to design and fabricate a multipurpose equipment during the year of 2021 in the Departmental Workshop of Farm Machinery and Power Engineering and evaluated at field of Dr. NTR College of Agricultural Engineering, Bapatla, Andhra Pradesh, India. The proposed design of machine is economical to fabricate, and have greater design simplicity than its counterpart, with proper seed placement at desired depth, distance between rowsis adjusted because of tynes are fitted with the nut and bolts. Developed multipurpose equipment also done spraying and weeding attachment can be used simultaneously on single run in groundnut crop so that, the time and labour can be saved and it can be used for any narrow row crops for intercultural operations. The overall dimensions of developed multipurpose equipment are 1800×600×1550 mm and the weight of machine was 150 kg. The designed and develop machine was operated at various speeds i.e 1.8, 2.5 and 3.2 km h-1. The field efficiency while doing sowing, spraying and weeding of equipment varies from 78,83 and 78% at 1.8, 2.5 and 3.2 km h-1. The different operations were operated effectively at 2.5 km h-1. The use of multipurpose equipment helps to overcome the problems of drudgery, labour shortage timeless of operation and as a result, the farm power availability in farms can be increased. Hence, there is a need for a multipurpose implement for carrying different operations in groundnut crop.

Optimizing agronomic practices for hard winter wheat production in the Great Plains with respect to seeding rate, row spacing, and variety

AbstractWinter wheat (Triticum aestivum L.) yield in dryland areas is optimized by the improvement of genetics in combination with ideal production practices. Different combinations of seeding rate and row spacing can influence the development of wheat plants, impacting wheat yield and its components. To determine the influence of these practices, yield components, water use efficiency (WUE), biomass, and subsequent grain yield were evaluated in an experiment conducted at the High Plains Agricultural Laboratory, Sidney, NE, from 2019 until 2022, using a split‐plot randomized complete block design with four replications. Treatments consisted of four different row spacings (19, 25, 31, and 51 cm), three seeding rates (1.05, 2.1, and 3.1 million seeds ha−1), and two high performing winter wheat varieties—‘Ruth’ and ‘Robidoux’. Row spacing showed differences in wheat yield (p < 0.0001) across all years, with a significant effect of seeding rate only in 1 year and an interaction effect of the three factors in 2022 alone. Higher wheat yield was achieved with the two narrower row spacings (19 and 25 cm) compared to the wider row spacings of 38 and 51 cm. The treatment combining the 19 cm row spacing and either 2.1 or 3.1 million seed ha−1 seeding rate had the greatest yields in most years. Narrower row spacings had improved WUE in drier years as compared to wider row spacings.

Does narrow row spacing suppress weeds and increase yields in corn and soybean? A meta-analysis

AbstractNarrow row spacing (<76 cm) could improve crop competitiveness, suppress weeds and might provide yield advantage. Many studies have been conducted to evaluate the impact of narrow row spacing; however, no quantitative synthesis of these studies exists. The objectives of this meta-analysis were to (1) quantify the overall effect of narrow row spacing (<76 cm) on weed density, biomass, control, weed seed production, and yield in corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] compared with 76-cm row spacing, and (2) assess the influence of agronomic management decisions (tillage type, weed management, herbicide application frequency and time) on effect of narrow row spacing on weed suppression and corn and soybean yield. We compiled 1,904 pair-wise observations from 35 studies conducted in 12 states in the United States during 1961 to 2018. Averaged across individual observations, narrow row spacing suppressed weed density by 34%, weed biomass by 55%, and weed seed production by 45%, while it improved weed control by 32% and crop yield by 11% compared with 76-cm row spacing. Narrow row spacing in soybean suppressed weed density by 42%, weed biomass by 71%, and increased crop yield by 12% compared with 76-cm row spacing. Although narrow row spacing had a nonsignificant effect on response variables in corn, the number of studies (n = 1 to 6) and observations (n = 1 to 59) addressing each response variable were limited. Tillage type (conventional and reduced) did not influence the response of weed density, control, and seed production in narrow row spacing; however, weed biomass and weed seed production were more greatly reduced with the sequential application of herbicides compared with a single application. Thus, narrow row spacing in soybean can be integrated with other options for management of herbicide-resistant weeds.

Cultivation system influenced the critical period for weed control in cotton field

BackgroundThe critical period of weed control (CPWC) refers to the period of time during the crop growth cycle when weeds must be controlled to prevent yield losses. Ultra-narrow row (UNR) is a method of planting of cotton in rows that are 25 cm or less apart. Amongst cultural techniques for weed control, the use of narrow row spacing is considered to be a most promising approach that can effectively suppress weed growth and provide greater yields in cotton. This cultivation system can shorten the length of the critical weed-crop interference duration and results in greater yield. The current research aimed to determination of critical time of weed control in cotton (Gossypium hirsutum L.) under conventional and ultra-narrow row spacing conditions. Field experiments were arranged as factorial experiment in a randomized complete block design with three replications. Factors were cultivation system (conventional (50 cm row spacing) and ultra narrow row (25 cm row spacing and weed treatment including 30, 45, 60, and 75 days weeding after emergence during the growing season (weed free), and 30, 45, 60, and 75 without weeding (weed infested) in the growing season along with weedy and weed-free from sowing to harvesting. A four-parameter log-logistic model was fit to the two sets of relating relative crop yield to data obtained from increasing durations of weed interference and lengths of weed-free period.ResultsIn both years and cultivation systems, the relative yield of cotton decreased with the increasing duration of weed-interference but increased with the increasing duration of weed-free period. Ultra-narrow row cultivation delayed the beginning of the CPWC in cotton. Under ultra-narrow row condition, the CPWC ranged from 21 to 99 days after germination in 2021 and 23 to 91 days in 2022 based on the 5% acceptable yield loss. Under conventional cultivation CPWC ranged from 17 to 102 days after emergence in 2021 and 18 to 95 days after emergence in 2022.ConclusionsUnder both conventional and Ultra-narrow row conditions, weed interference reduces seed yield. Under ultra-narrow row condition, weed interference until 21.1–23.5 days after cotton emergence and under conventional condition, weed interference until 16.9–18.5 days after cotton emergence had not significant reduction on cotton yield.

Quadrat misuse: Confessions of a cover crop researcher's biomass sampling journey

AbstractRectangular quadrats (1 m2 or less) are commonly used in cover crop research to sample shoot biomass in fields where the cover crops are planted in narrow rows. However, in drilled cover crops, quadrats do not accurately estimate cover crop biomass unless the width dimension of the quadrat, that runs perpendicular to the rows, is a multiple of the cover crop row spacing. Illustrations are provided with correctly sized and placed quadrats for sampling drilled cover crops along with calculations to convert sampled biomass to field‐scale units. Examples with various quadrat sizes, row spacings, and quadrat placements are used to illustrate how researchers can inadvertently underestimate or overestimate biomass by up to 49% and 27%, respectively. A survey of 92 articles with cover crop biomass data published in the Agronomy Journal and Weed Technology from 2017 to 2021 found that many studies used an incorrect quadrat size, which suggests that they may have inaccurately estimated cover crop biomass. However, assumptions were made to reach this conclusion because only a few papers provided the dimensions, orientation, and shape of the quadrat used. These results (1) raise important questions about possible errors made in papers reporting cover crop biomass data and associated metrics (nitrogen uptake, weed biomass, etc.), and (2) highlight the need for describing sampling methods in greater detail to ensure that accurate data and analysis are published in the literature. Approaches to correct possible errors in published research are described along with biomass sampling suggestions for future cover crop research.

Contributions of shading, soybean (Glycine max) row width, and planting green on horseweed (Conyza canadensis) management compared with soil-applied residual herbicides

AbstractGlyphosate-resistant (GR) horseweed is a problematic weed for Michigan soybean growers. Additionally, rosette- and upright-horseweed growth types have been observed co-emerging during mid- to late summer in several Michigan fields. In the greenhouse, shade levels from 35% to 92% reduced rosette- and upright-horseweed biomass 31% to 99% compared with the upright growth type grown under 0% shade. Greater reductions in biomass occurred under 69% and 92% shade. Thus, increased shading by planting in narrow rows and/or planting green into cereal rye may improve horseweed suppression. A field experiment conducted over 3 site-years compared the effect of fall-planted cereal rye terminated with glyphosate 1 wk after planting (WAP; planting green) with a preemergence residual herbicide program (glyphosate + 2,4-D + flumioxazin + metribuzin) on horseweed control in soybean planted in three row widths (19, 38, and 76 cm). Planting green or applying a residual herbicide program across all row widths reduced horseweed biomass 86% to 91% and 95% to 99%, respectively, compared with soybean planted with no cover in 76-cm rows, 4 to 6 WAP. At soybean harvest, when a noneffective postemergence herbicide (glyphosate) was applied, horseweed biomass was 42% and 81% lower by planting green or applying a residual-herbicide program compared with no cover, respectively. Similarly, planting soybean in 19-cm rows reduced horseweed biomass compared with 38- and 76-cm rows. When an effective postemergence program was applied, similar horseweed biomass reductions were observed by planting green or applying a residual herbicide across all row widths. Additionally, soybean yield and economic returns were similar between planting green and applying a residual herbicide in 1 of 2 site-years. Integrating planting green and an effective postemergence herbicide program offers an alternative horseweed management strategy to applying a residual preemergence herbicide program.

Using soybean chaff lining to manage waterhemp (Amaranthus tuberculatus) in a soybean–corn rotation

AbstractWaterhemp (Amaranthus tuberculatus[Moq.] Sauer) escapes are common in midwestern U.S. soybean [Glycine max(L.) Merr.] fields due to the continued rise in herbicide-resistant (HR) populations. In a conventional harvesting system, weed seeds are harvested with the crop grain and spread back on to the field. Harvest weed seed control methods such as chaff lining concentrate weed seed-bearing crop and weed chaff into a narrow row (chaff line). These chaff lines (30- to 50-cm wide) are undisturbed the following growing seasons, under the assumption that the chaff line creates an environment less favorable for weed seed germination and survival. Field experiments were conducted in a soybean–corn (Zea maysL.) rotation in 2020 and 2021 in Ames, IA, and Roland, IA, to quantify the effectiveness of chaff lining for managingA. tuberculatusseeds. About 70% of theA. tuberculatusseeds were retained on the mother plant at soybean harvest in 2020. The chaff lining system concentrated more than 99% of theA. tuberculatusseeds exiting the combine into the chaff line. AlthoughA. tuberculatuspopulation density in 2021 was 76% higher inside the chaff line than outside the chaff line,A. tuberculatusaboveground biomass was 63% lower inside the chaff line than outside the chaff line at 12 wk after corn planting. Similarly,A. tuberculatusinside the chaff line had delayed emergence compared withA. tuberculatusoutside the chaff line. Application of preemergence herbicides in corn inside the chaff line delayedA. tuberculatusemergence by more than 2 wk compared withA. tuberculatusoutside the chaff line. Additionally, a follow-up postemergence herbicide application in corn was needed only inside the chaff line to manageA. tuberculatus, suggesting the possibility of lower overall herbicide use. These results support implementing chaff lining in soybean-based crop systems of the U.S. Midwest to help manage HRA. tuberculatusseedbanks.

Optimal planting pattern of cotton is regulated by irrigation amount under mulch drip irrigation.

It is of great importance to explore agronomic management measures for water conservation and cotton yield in arid areas. A four-year field experiment was conducted to evaluate cotton yield and soil water consumption under four row spacing configurations (high/low density with 66+10 cm wide, narrow row spacing, RS66+10H and RS66+10L; high/low density with 76 cm equal row spacing, RS76H and RS76L) and two irrigation amounts (CI:conventional drip irrigation; LI:limited drip irrigation) during the growing seasons in Shihezi, Xinjiang. A quadratic relationship was observed between the maximum LAI (LAImax) and seed yield. Canopy apparent transpiration rate(CAT), daily water consumption intensity (DWCI) and crop evapotranspiration (ETC) were positively and linearly correlated with LAI. The seed yields, lint yields, and ETC under CI were 6.6-18.3%,7.1-20.8% and 22.9-32.6%higher than those observed under LI, respectively. The RS66+10H under CI had the highest seed and lint yields. RS76L had an optimum LAImax range, which ensured a higher canopy apparent photosynthesis and daily dry matter accumulation and reached the same yield level as RS66+10H; however, soil water consumption in RS76L was reduced ETC by 51-60 mm at a depth of 20-60 cm at a radius of 19-38 cm from the cotton row,and water use efficiency increased by 5.6-8.3%compared to RS66+10H under CI. A 5.0<LAImax<5.5 is optimum for cotton production in northern Xinjiang, and RS76L under CI is recommended for high yield and can further reduce water consumption. Under LI, the seed and lint yield of RS66+10H were 3.7-6.0% and 4.6-6.9% higher than those of RS76L, respectively. In addition, high-density planting can exploit the potential of soil water to increase cotton yields under water shortage conditions.

Influences of 13 Years New Conservation Management on Labile Soil Organic Carbon and Carbon Sequestration in Aggregates in Northeast China

New conservation management (NCM) for summer maize monocultures might cause changes in the organic carbon composition when compared with conventional tillage (CT). To investigate the difference, the soil organic carbon (SOC) under 13 years of NCM and CT was studied in Northeast China. The NCM involved the use of a 40 cm and 160 cm narrow-wide row (maize was planted in the narrow row in two lines) with straw retained, but with no tillage and change in ridge direction. SOC in different soil aggregate size classes and labile organic carbon fractions at 0–10 cm, 10–20 cm and 20–40 cm depths were evaluated. The results showed that there was no significant difference in SOC content at a 0–10 cm depth, with values ranging from 19.9 to 21.1 g·kg−1 between two management systems. The contents of microbial biomass carbon (MBC) and light fraction organic carbon (LFOC) were significantly higher in NCM than in CT in the upper 10 cm. Among the labile organic carbon fractions, the light fraction organic C (LFOC) was the most sensitive to management change. The portion of macroaggregates (&gt;0.25 mm) was higher under NCM than under CT and decreased with the increase in soil depth. NCM improved the organic carbon storage in aggregates 1–0.5 mm and reduced the organic carbon storage in microaggregates. It was concluded that NCM would be an effective and useful management choice for the enhancement of soil C sequestration in maize field systems in Northeast China.

Row spacing and phosphorus use efficiency in no-tillage maize

Reduced row spacing has shown to increase maize (Zea mays L.) nitrogen (N) use efficiency, but little is known about it effects on phosphorous (P) use efficiency (PUE). The objective of this study was to evaluate the PUE of maize under reduced row spacing and varying N regimes. No till maize was grown in Balcarce, Argentina, during two growing seasons using three rows spacing (35, 52, and 70 cm) and three N rates (0, 90, and 180 kg N ha−1). Shoot dry matter (DM), grain yield, and accumulated P content were determined. At V6 and R6 growth stages, the P use efficiency (PUE = g aboveground DM or grain yield per g P available) and it components P utilization efficiency (PUTE = g aboveground DM or grain yield per g P uptake), and P uptake efficiency (PUPE = g P uptake/g P available) were determined. N rate and narrower rows increased total DM, grain yield, and accumulated P content. Phosphorous concentration, PUTE, PUPE and PUE were not affected by row spacing or N rate. The present study showed that row spacing did not affect P use efficiency in no till maize when the soil P availability was adequate.

Effect of Row Spacing and Plant Density on Silage Maize Growth, Dry Matter Distribution and Yield

Maize growth in narrow rows provides a more uniform spatial arrangement, but it does not always lead to increasing yield. A four-year study was conducted to investigate the effect of row spacing on silage maize growth and yield during the growing season and at harvest time. A field experiment with conventional (0.70 m) and narrow rows (0.35 m) at a plant density of 92,000 plants ha−1 was evaluated in the years 2011–2014, and the interaction of row spacing × plant density (92,000 and 110,000 plants ha−1) was tested in 2013–2014. The narrow rows clearly demonstrated potential to support plant height and weight development, together with a higher stalk proportion, at around two months after seeding. However, these contrasts were lost in the later stages and at harvest time. Some potential for non-significantly higher dry matter yield (4.6–10.8%) was shown in the narrow rows in three years of the experiment, in association with lower losses in plant numbers, when compared to conventional row spacing. The potential of yield improvement in the narrow rows showed relationships with weather conditions during the second half of the growing season. In summary, under the growing conditions of the study region, narrow row spacing significantly promoted early plant development, but these effects did not persist until harvest, thus resulting in only limited success in yield improvement.

Summer pulses as sources of green manure and soil cover in the U.S. Southern Great Plains

Winter wheat (Triticum aestivum L.) – summer fallow rotations in the Southern Great Plains (SGP) have numerous sustainability issues, such as low precipitation use efficiencies and increased soil erosion. Replacing summer fallow with a legume grown as a green manure would help reduce soil erosion, improve precipitation use efficiency, and add nitrogen (N) credits for the subsequent wheat crop. A two-year field experiment evaluated the capabilities of three summer pulses: soybean [Glycine max (L.) Merr.], moth bean [Vigna aconitifolia (Jacq.) Marechal], and tepary bean [Phaseolus acutifolius (A.) Gray] to serve as green manures and soil cover. We examined their performance across two row spacings (38 and 76 ​cm) and two moisture regimes (rainfed and irrigated). Narrow row spacing (38 ​cm) provided greater canopy cover, aboveground biomass, and N accumulation than the broad row spacing (76 ​cm) during the early growing season. Among species, tepary bean demonstrated consistent and higher canopy cover early in the season. Soybean produced the highest aboveground biomass (5,327–8,855 ​kg ​ha−1) and N accumulation (115–269 ​kg ​ha−1) among the three pulses. Multilinear regression (MLR) models suggested that canopy height and canopy cover could estimate both aboveground biomass (R2 ​= ​0.62) and N accumulation (R2 ​= ​0.55) for tested pulses. Based on results, soybean was the most promising choice among tested pulses, considering its higher aboveground biomass and N accumulation. Modelling studies to simulate growth of these crops with long-term weather scenarios are encouraged to identify the most reliable cover crop for different areas of the SGP.

Root Characteristics for Maize with the Highest Grain Yield Potential of 22.5 Mg ha−1 in China

In maize (Zea mays L.), rational root structure promotes high grain yield under dense sowing conditions. This study was conducted at Qitai Farm in Xinjiang, China, in 2019 and 2021. A traditional wide and narrow row planting method was adopted, with wide rows of 0.7 m and narrow rows of 0.4 m. The cultivars DH618 and SC704, which have grain yield potentials of 22.5 and 15 Mg ha−1, respectively, were selected for study of the root structure and distribution characteristics under high-yield and high-density planting conditions. The highest yield (20.24 Mg ha−1) was achieved by DH618 under a planting density of 12 × 104 plants ha−1. The root structure of DH618 was well developed at that planting density, and the root dry weight (RDW) was 17.49 g plant−1 and 14.65 g plant−1 at the silking and maturity stages, respectively; these values were 7.56% and 11.86% higher, respectively, than those of SC704. At the silking stage, the proportions of RDW at soil depths of 0–10, 10–20, 20–40, and 40–60 cm were 66.29%, 11.83%, 16.51%, and 5.38%, respectively, for DH618; over the 20–60 cm soil layer, this was an average of 4.04% higher than the RDW of SC704. At maturity, the proportions of RDW at soil depths of 0–10, 10–20, 20–40, and 40–60 cm were 61.40%, 11.19%, 17.19%, and 10.21%, respectively, for DH618, which was an average of 9.59% higher than that of SC704 over the 20–60 cm soil layer. At maturity, DH618 roots were mainly distributed in the narrow rows, accounting for 72.03% of the root structure; this was 9.53% higher than the roots of SC704. At silking and maturity, the root weight densities of DH618 were 471.98 g m−3 and 382.98 g m−3, respectively (5.18% and 5.97% higher, respectively, than the root weight densities of SC704). The root lengths of DH618 were 239.72 m plant−1 and 199.04 m plant−1 at the silking and maturity stages, respectively; these were 16.45% and 25.39% higher, respectively, than the root lengths of SC704. The root length densities were 0.58 cm cm−3 and 0.46 cm cm−3 at the silking and maturity stages, respectively, and these were 16.86% and 17.08% higher, respectively, than the root length densities of SC704. This study indicated that the maize hybrid DH618 had a more developed root structure with increased root distribution in the deep soil and narrow rows under high-density planting compared to cultivar SC704, contributing to high grain yield under dense planting.

Multi-tactic strategies to manage herbicide-resistant waterhemp (Amaranthus tuberculatus) in corn–soybean rotations of the U.S. Midwest

AbstractField experiments were conducted over 2 yr (2019 to 2020) at two locations in Iowa to evaluate multi-tactic strategies for managing multiple herbicide–resistant (MHR) waterhemp [Amaranthus tuberculatus (Moq.) Sauer] in a corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] rotation. The effect of three herbicide programs on A. tuberculatus control was tested in corn (2019). The effects of the prior year’s corn weed control, a cereal rye (Secale cereale L.) cover crop, and soybean row spacing (38-cm vs. 76-cm wide) on A. tuberculatus density, biomass, and seed production were tested in soybean (2020). A herbicide program used in corn with two sites of action provided only 35% control of MHR A. tuberculatus compared with ≥97% control by a herbicide program with three sites of action. In soybean, adequate control of A. tuberculatus (≥90%) in the prior year’s corn crop and use of a cover crop or narrow rows reduced A. tuberculatus density by more than 60% at 3 and 9 wk after planting (WAP) compared with inadequate control (30%) in the prior year’s corn and no cover crop. Cover crop and narrow-row soybean reduced A. tuberculatus density by 44% at 3 WAP compared with no cover crop and wide-row soybean. Inclusion of a single control tactic, adequate control (≥90%) with multiple herbicides in the prior year’s corn, use of a cover crop, or narrow-row soybean reduced A. tuberculatus biomass and seed production at soybean harvest by at least 24% compared with inadequate control (30%) in the prior year’s corn, no cover crop, and wide-row soybean. The combination of all three control tactics reduced A. tuberculatus biomass and seed production at soybean harvest by at least 80%. In conclusion, diverse control tactics targeting A. tuberculatus at multiple life-cycle stages can make substantial contributions to the management of MHR populations.

Interaction of genotype-ecological type-plant spacing configuration in sorghum [Sorghum bicolor (L.) Moench] in China.

Grain sorghum has been a significant contributor to global food security since the prehistoric period and may contribute even more to the security of both food and energy in the future. Globally, precise management techniques are crucial for increasing grain sorghum productivity. In China, with diverse ecological types, variety introduction occasionally occurs across ecological zones. However, few information is available on the effect of ecological type on genotype performance and how plant spacing configuration influences grain yield in various ecological zones. Hence, a series of two-year field experiments were conducted in 2020 and 2021 in four ecological zones of China, from the northeast to the southwest. The experiments included six widely adapted sorghum varieties under six plant spacing configurations (two row spacing modes: equidistant row spacing (60cm) mode and wide (80cm)-narrow (40cm) row spacing mode; three in-row plant spacings: 10cm, 15cm, and 20cm). Our results indicated that ecological type, variety, and plant spacing configuration had a significant effect on sorghum yield. Ecological type contributed the highest proportion to the yield variance (49.8%), followed by variety (8.3%), while plant spacing configuration contributed 1.8%. Sorghum growth duration was highly influenced by the ecological type, accounting for 87.2% of its total variance, whereas plant height was mainly affected by genotype, which contributed 81.6% of the total variance. All test varieties, developed in the south or north, can reach maturity within 94-108d, just before fall sowing in central China. Generally, sorghum growth duration becomes longer when a variety is introduced from south to north. A late-maturing variety, developed in the spring sowing and late-maturing regions, possibly could not reach maturity in the early-maturing region. The row spacing modes had no significant affect on sorghum yield, but the equal-row spacing mode consistently caused higher yields with only one exception; this might imply that equal-row spacing mode was more advantageous for boosting sorghum yield potential. In contrast, decreasing in-row plant spacing showed significant positive linear associations with sorghum grain yield in most cases. In addition, these results demonstrated that sorghum is a widely adapted crop and enables success in variety introduction across ecological zones.

Optimization of Operation Parameters of the Garlic Plant Divider and Lifter Mechanisms

The technology of the divider and lifter mechanisms of a garlic harvester using the depth limit, straw divide, and straw lift modes was studied in Lanling County, Shandong Province, China, according to the characteristics of high hardness, good uprightness and narrow row spacing of garlic planting. A test prototype of the divider and lifter mechanisms of the garlic harvester was designed and manufactured. Single-factor experiments and orthogonal regression experiments were carried out using the experimental factors of working speed, the angle of the divider, the height of the tip of the divider’s tooth from the ground, the ratio of the lifter’s speed to working speed and the length of the lifter’s tooth. The index was the success rate of feed. The results showed that the working speed, the angle of the divider and the length of the lifter’s tooth had a significant influence on the success rate of feed (p &lt; 0.05), but the experimental factors of the height of the tip of the divider’s tooth from the ground and the ratio of the lifter’s speed to working speed did not have a significant influence on the success rate of feed (p &gt; 0.05). The effects of the angle of the divider, the working speed, and the length of the divider’s tooth on the success rate of feed decreased in significance. When the working speed was 0.72 km·h−1, the length of the lifter’s tooth was 343.5 mm and the angle of the divider was 20°, the success rate of feed was the highest (98.18%). The research results are conducive to promoting high-quality and efficient combined harvesting of garlic in Lanling County, Shandong Province, China.

Physical Properties and Germination Characteristics of Black Carrot Seeds of Kırıkhan Local Cultivar in Ereğli District of Konya Province

Black carrot production is an important agricultural activity for local farmers of Ereğli and Karapınar districts of Konya province. About 20% of the black carrots produced are used in turnip industry and 80% is used in concentrate production. The color value of black carrots of Kırıkhan local cultivar is higher than that of black carrots of Ereğli cultivar. Therefore, concentrate companies prefer the local cultivar of Kırıkhan in Ereğli and Karapınar Districts of Konya. In this study, some physical properties of black carrot seeds of local population of Kırıkhan cultivar were determined and seeds were sown at three different on-row seed spacings (2.5, 5 and 7.5 cm). Sowing was performed on ridges in three narrow rows as to have 7.5 cm between the rows and at a forward speed of 0.64 m s-1. Average length values of the classified bare and coated black carrot seeds were respectively determined as 3.52 and 4.02 mm, geometric mean diameter values as 1.65 and 2.31 mm, sphericity values as 47.49 and 58.73%, thousand-seed weights as 2.20 and 6.67 g, germination rate values as 82.50 and 76.30%. Fracture resistance value of the coated seeds was measured as 4.89 Nmm-2, water dissolution time as 18.48 s and one-seed ratio in coating as 96%. In field trials conducted at different sowing distances, average germination time of classified bare seeds and coated seeds were repectively determined as 9.40 and 9.18 days, germination rate index values as 1.688 and 1.547 [plant (m day)-1] and the field emergence rate values as 54.15 and 52.39%.

Increasing the productivity of rajma through proper sowing date and plant geometry

Rajma (Phaseolus vulgaris L.) cultivation is gaining popularity in Terai to Hills of Nepal. The poor plant establishment and yield due to the results of unsuitable sowing time and row spacing are the main reasons for lower productivity of it. Therefore, the date of sowing and row spacing trials were conducted in two consecutive years, 2017 and 2018 at the Grain Legumes Research Program, Khajura, Banke. A widespread and registered variety of rajma PDR 14 was used in the experiment. The experiment was laid out in a split-plot design with four sowing dates (a) 11th October, (b) 26th October, (c) 10th November and (d) 25th November as the main-factor, and three rows spacing (a) 30 cm, (b) 40 cm and (c) 50 cm as the sub-factor, consisted of three replications. The effect of the date of sowing on all the yield and yield attributing characters was found significant at a one percent significance level. Similarly, row spacing has resulted in a significant difference in grain yield. Rajma sown on 26th October (Kartik 9) produced 12, 38 and 64% higher grain yield than sown on 11th October, 10th November and 25th November, respectively. Moreover, rajma seeds sown on 26th October with 30 cm × 10 cm plant geometry produced the highest grain yield (2185 kg/ha). The narrow row spacing seemed well than the wider row in rajma production. There is a great potential to increase the production and productivity of rajma through an appropriate time of sowing and row spacing.

THE EFFECTS OF SOWING DESIGNS ON FORAGE YIELD AND QUALITY OF SWEET SORGHUM AND MUNG BEAN MIXTURES UNDER MEDITERRANEAN CONDITIONS

This study was conducted to determine the effects of sowing designs on forage yield and quality in sweet sorghum and mung bean grown as binary mixture with different cultivation systems in Mediterranean conditions under second crop season during 2019-2020. As sowing design, twin-row (20×55 cm row spacing), narrow-row (55 cm row spacing) and conventional-row (75 cm row spacing) were used as sowing design. The mixtures were formed based on the plant density and alternative row numbers of sweet sorghum and mung bean. Sowing was done on alternating rows of 1 row of sweet sorghum and 1 row of mung bean and 2 rows of sweet sorghum and 1 row of mung bean. The plant density of sweet sorghum was 14 plants m-2 and plant densities of mung bean were 14 plants m-2, 21 plants m-2 and 28 plants m-2. This experiment was planned as two-factor (sowing designs and mixtures) and conducted in randomized complete block design arranged in split plot with 3 replications. To evaluate the forage yield and quality, fresh forage yield, dry matter yield, NDF, ADF, ADL, crude ash crude protein and ether extract characteristics were examined. In addition, the intercropping potential of mung bean and sweet sorghum mixtures was evaluated by the land equivalent ratio. As a result of the present study, mixed cultivation of 14 plants m-2 with one row of sweet sorghum and 14 plants m-2 with one row of mung bean gave the best results in narrow row sowing design. It was concluded that an efficient and high quality intercropping system can be realized in the second crop conditions in regions where Mediterranean climatic conditions prevail, especially for mung beans and sweet sorghum.

On-farm evaluation of UAV-based aerial imagery for season-long weed monitoring under contrasting management and pedoclimatic conditions in wheat

Timely availability of weed infestation maps is a key prerequisite for the implementation of site-specific weed management practices. Low-altitude aerial imagery obtained from unmanned aerial vehicles (UAVs) has shown significant potential for weed detection in crops. However, most studies focused on wide-spaced row crops such as maize and sunflower and evaluated proposed methods on single or few well-characterized experimental sites at specific points in time representing a limited range of application scenarios. This study evaluated the feasibility of weed detection in on-farm wheat fields characterized by a narrow row spacing, throughout the early and late developmental stages using UAV imagery and ground-based high-resolution imagery. Image data was obtained for nine sites, representing a wide range of management and pedoclimatic conditions. These sites can be seen as a representative sample of scenarios that would be encountered in practice. A high within- and across-site as well as temporal variation was observed for weed infestation levels and weed population species composition, highlighting the need for spatially and temporally resolved weed mapping. Image-based classification of vegetation objects as crop or weed plants was achieved with an accuracy of 0.88 and 0.72 in ground-based high-resolution images and UAV-based aerial images captured from an altitude of 10 m, respectively. The accuracy of pixel-wise, vegetation-index-based weed infestation estimation during the late vegetative stages varied strongly across sites. Our results highlight the critical importance of a high ground resolution for weed detection using object-based image analysis during the critical growth stages of wheat and of robust methods that are applicable across a range of scenarios. This suggested that future research aiming at a rapid implementation of site-specific weed management in wheat should focus on the development of ground-based systems. Yet, aerial monitoring of wheat stands during late developmental stages using currently available equipment offers significant potential for reducing weed pressure with site-specific weed control measures in the context of crop rotations.