Droplet size spectra and drift effect of two phenmedipham formulations and four adjuvants mixtures

The effect of 4 adjuvants on two formulations of phenmedipham (EC and SC) applied with three types of hydraulic nozzles (hollow cone, flat fan and air induction) was evaluated using a wind tunnel to determine spray drift potential (DP). The volume median diameter (VMD) and the percentage by volume of droplets less than 100 μm diameter was determined using a Malvern particle size analyser. In a wind tunnel DP was measured between 2 and 6 m downwind of the nozzle on glass fibre collectors using a fluorescent tracer. The EC formulation produced a smaller VMD and larger DP than the SC formulation irrespective of any effect due to adjuvants. DP increased as the proportion of small droplets increased.     

Rotary atomiser design requirements for optimum pesticide application efficiency

Pesticide application efficiency from aircraft could be increased substantially, and required downwind buffer distances to avoid drift damage reduced significantly, if sharp issuing points or pins were added to existing rotary cage atomizer designs. This would enable existing rotary cage units, already successfully deployed for Ultra Low Volume (ULV) applications of insecticides, to be also used for Large Droplet Placement (LDP) application of herbicides. Studies at Cranfield University using high speed photography and laser droplet sizing instrumentation demonstrated that the addition of fine pins to the final atomizing surface of the rotating cage would increase uniformity of droplet production, by promoting fluid atomization in the ligament mode. This would lead to a substantially increased percentage of droplets in the spray falling between 100 μm and 300 μm in size, suggested here as a biological/environmental droplet size optimum. Development of a ‘spinning pins’ rotary atomizer for aircraft would therefore be highly desirable for agricultural and other purposes. Investment in this technology has the potential to significantly reduce pollution of atmosphere, soil, fresh water and oceans with pesticides.     

灌浆期六旋翼无人机喷幅和喷液量对玉米群体内雾滴沉积分布、漂移特性的影响

采用大疆T30无人机在玉米灌浆期进行喷施作业,探讨喷幅和喷液量对雾滴在群体内沉积分布影响。采用两因素试验设计,设置3个喷幅[4(G1)、5(G2)、6.5 m (G3)]和5个喷液量[15、30、45、60、75 L/hm²(R1～R5)],将玉米群体从上至下分为5层(A～E)。结果表明,在不同喷幅和喷液量处理组合下,随着喷液量增加,雾滴总沉积量、覆盖率、覆盖密度显著增加,随着喷幅的升高呈先增后降的趋势,其中G2R5、G3R5和G1R5处理的雾滴总沉积量较大,但雾滴的地面损失量增多、沉积量均匀性和穿透性不佳、漂移加重,总体上G2喷幅下各叶层的雾滴沉积分布较优。在实际生产中喷液量选择不宜过大,应结合施药属性及农田环境等因素,确定适宜的喷液量。     

Relative drift potential and droplet size spectra of aerially applied Propanil formulations

Wind tunnel studies were carried out using a Malvern (Malvern Instruments, Spring Lane South, Malvern, UK) laser particle size analyser to measure the droplet size spectra produced by an emulsifiable concentrate (EC), a water dispersable granule (WDG) and a liquid flowable (LF) formulation of Propanil with and without a non-ionic surfactant or a crop oil. The relative drift potential of each combination of formulation and adjuvant was determined in the field by measuring the relative recovery on vertical strings, placed 61 m downwind, for formulations sprayed simultaneously from a Cessna Ag Husky airplane, using a twin-tracer fluorescent dye technique. Differences were observed in the droplet size spectra and the relative drift potential of the three formulations and two adjuvants. Under the conditions of this study, there was a 25% difference in droplet size and a fivefold change in drift potential between the formulation types. The EC formulation produced the smallest vmd and the greatest amount of drift.     

Pressure,droplet size classification,and nozzle arrangement effects on coverage and droplet number density using air-inclusion dual fan nozzles for pesticide applications

Spray applications are most effective when they cover the greatest per unit area, improving target pest control. In order to optimize spray applications, nozzle companies have developed new designs that seek to provide the greatest and most uniform coverage per target unit area. While dual fan nozzles have been examined against single fan nozzles in several studies, there has not been a comprehensive comparison of multiple nominal flow rate and multiple dual fan nozzle types. This study sought to examine pressure, droplet size classification, and nozzle arrangement effects on droplet number density on horizontal artificial collectors using a fixed application rate. The relationship between coverage and nozzle type was significant (P < 0.001) as was the relationship between coverage and pressure (P < 0.001). The 207 kPa pressure resulted in the highest coverage for every nozzle type except the alternating TADFs (ATADF)s. The GAT 11003 resulted in the highest coverage overall with 39.6% at the 207 kPa pressure, followed by the TADF 11005 and TADF 11003 at 38.6% and 38.3% coverage respectively. The effect of pressure was significant for the droplet number density (P < 0.001) as was the effect on droplet number density from nozzle type (P < 0.001). The 414 kPa pressure resulted in the highest droplet number density for all nozzle types except the AITTJ 11003 and the MDD 11004. The GAT 11003 and GAT 11004 produced the highest overall droplet number densities with 73.0 and 72.6 droplets cm² at the 414 kPa pressure. The GAT 11003 had the greatest droplet number density at every pressure. Nozzle arrangement has a significant effect on spray coverage with asymmetric dual fan nozzles, and it would be recommended to alternate these nozzles on a spray boom to increase coverage especially at higher application speeds. Results from this study show that an applicator can select a coarser droplet size classification without observable loss in coverage, while greatly reducing the drift potential of the application.     

Comparative performance of recycling tunnel and conventional sprayers using standard and drift-mitigating nozzles in dwarf apple orchards

The use of tunnel sprayers should be encouraged because they can potentially reduce pesticide input and drift in orchards. They could also allow smaller plot size in multifactorial trials in which fully randomized or randomized block designs are recommended. However, the effectiveness of plant protection products applied with tunnel sprayers cannot be reliably assessed without a thorough investigation into spray distribution in tree canopies. A set of three experiments was undertaken in an apple orchard to compare a new type of recycling tunnel sprayer with a standard axial fan sprayer, both of them fitted with either conventional hydraulic hollow cone nozzles (ATR) or drift-mitigating air induction cone nozzles (TVI). Its performance was assessed in terms of 1) spray deposit and coverage in the canopy, 2) sedimentation drift (spray drift to the ground) and 3) collection and recycling rate of the liquid sprayed in the tunnel. Artificial targets composed of cellulose papers and water-sensitive papers were used to evaluate the spray deposit and coverage at similar target positions for each treatment. A fluorescent dye was used as the spray tracer.     

QTL analysis of kernel size and shape in two hexaploid wheat mapping populations

Kernel size and shape in wheat are important because of their relationship with yield and milling quality. This paper reports QTL analyses of kernel morphology in two hexaploid wheat mapping populations, grown in NY and CA. Kernel morphology was evaluated through a new and improved method, combining measurements from two orthogonal pictures. Single marker regression showed that several genomic positions, scattered through the genome, were related to kernel size and shape, in both populations. The direction of allele effects was consistent between environments, although the LOD scores varied considerably. Composite interval mapping revealed QTLs on all seven homoeologous groups, considering both populations. For the QTLs detected through this method, the signal and magnitude of additive effects were similar between environments, indicating small QTL × environment interaction. In the population W7984 × Opata 85, the strongest signal was detected on the chromosome 5B, for kernel length. In the population AC Reed × Grandin, the most important QTLs were detected on chromosome 2D, affecting the lateral dimensions of the kernel. This study agreed with previous reports that the genetic control of kernel length and width are largely independent. Additionally, it was shown that QTLs detected on different mapping populations, with identical evaluation methods, can be very distinct.     

No relationship between leaf size and yield in medium leaf size white clover varieties under rotational sheep grazing and cutting

Nine medium leaf size varieties of white clover ( Trifolium repens L.) were grown in field plots with perennial ryegrass ( Lolium perenne L.) variety Fennema, and yield measurements were taken under both cutting and rotational sheep grazing. The sampling and management protocols in the cut plots mirrored those for the National List testing of white clover varieties in the UK. Dry-matter yields of the white clover and perennial ryegrass components of the mixture were recorded for six cuts in each of three harvest years. White clover yields were highest under cutting, perennial ryegrass yields under grazing. Significant differences were seen between the yields of white clover varieties, and significant interactions between white clover yields and management type were also observed. This interaction effect was not seen with respect to perennial ryegrass yields. No correlation was observed between leaf size and white clover dry-matter yield under either management type. The results suggest that leaf size, on the scale of variation represented within a leaf size category, is not a good predictor of yield under rotational sheep grazing or cutting. The significance of these results for varietal evaluation and for ascertaining the underlying bases for yield differences is discussed.     

Nutrient composition of groundnut cultures (Arachis hypogaea L.) in relation to their kernel size

Seven varieties of groundnuts of varying kernel size were selected to study the relation between kernel size and nutritional quality. Results indicated that no significant (r=0.22) difference was found in oil contents among the various varieties which ranged from 46–52 percent. Protein contents ranged from 17–25.2 percent. Protein content of small seed varieties was high compared to bold seeded varieties, whereas sugar content of bold seeded varieties was higher. No significant differences in amino acid and fatty acid compositions were observed among the varieties tested. In vitro digestibility of protein tended to be slightly less but not significantly so in bold seeded varieties compared to small and medium size varieties. Niacin content of bold seeded varieties was slightly higher compared to other varieties.     

多效唑在园艺植物上的应用

多效唑（PP333）是一种植物生长延缓剂,在园艺植物上的应用非常广泛。PP333可明显促进草坪草的分蘖,控制果树枝梢生长及矮化、促进花芽分化、增加花量,还可增加花卉植物叶绿素含量,促进根菜类蔬菜增产、叶菜类蔬菜延后花期。本研究总结了PP333在园艺植物上的应用,并提出PP333使用过程的注意事项。     

Comparative effects of pesticides,fenitrothion and fipronil,applied as ultra-low volume formulations for locust control,on non-target invertebrate assemblages in Mitchell grass plains of south-west Queensland,Australia

The effect of an aerial application of two broad-spectrum insecticides, the organophosphorus compound, fenitrothion, and the phenyl pyrazole pesticide, fipronil, on non-target invertebrates was investigated during Australian plague locust (Chortoicetes terminifera, (Walker, 1870)) control operations on a Mitchell grass (Astrebla spp.) plain in south-western Queensland, Australia, between 2002 and 2004. The invertebrate assemblages were monitored using yellow pan and Malaise traps to target flying invertebrates and pitfall traps to target ground-dwelling invertebrates, sampled immediately before spraying and then at 3, 7, 39, 79, 189 and 414 days after spraying. Both pesticides caused significant changes to invertebrate community composition immediately after spraying, largely due to changes in the abundance of Orthoptera, Collembola and Formicidae. The richness and abundance of invertebrates in Malaise and yellow pan traps did not differ significantly with pesticide application although significant changes in assemblage composition persisted for up to 79 days. Although not statistically significant, the richness and abundance of invertebrates in pitfall traps declined at sprayed sites after treatment, relative to controls. Assemblage composition in pitfall traps at sprayed sites was significantly different from that in the control sites and these differences persisted for up to 189 days post-spray. Prolonged drought across the study site is likely to have affected the recovery of invertebrate populations and a return to pre-spray abundances did not occur until after heavy rain fell approximately one year after the commencement of the study. The controlling influence of climatic conditions on recovery of non-target arthropod populations after exposure to pesticides therefore has implications for risk assessments for the use of pesticides in arid environments.     

Effect of heating temperature on the particle size distribution in waxy wheat flour

The particle size of waxy (amylose-reduced) wheat (Triticum aestivum L.) starch was determined at isothermal temperatures by laser diffraction analysis. Flour samples were suspended in deionized water at temperatures ranging from 30 to 90 °C for 20–60 min. At 30 °C, all of the flour particles exhibited trimodal size distributions, i.e., the particles in the first, second, and third modes were <10 μm, 10–50 μm, and 51–300 μm, respectively. Control experiments with isolated starch indicated that the first and second modes were associated mainly with starch granules, whereas the third mode may have been related to gluten and gluten adhesion. The particle size distributions of waxy segregant wheat flours were temperature dependent. At 60 °C, there were significant changes in the particle size and distribution of waxy flours, which indicated the swelling of starch granules in response to elevated temperature. As the temperature increased, the peak particle size of waxy segregant wheat flours increased in different ways. The results suggest that variations in the swelling properties of selected waxy genotype flours may be due to the strength of starch–protein interaction and the capacity for starch granule gelatinization.     

Boll size affects the insecticidal protein content in Bacillus thuringiensis (Bt) cotton

Bacillus thuringiensis (Bt) transgenic cotton has been planting in large-scale for more than 10 years in China. It was observed that resistance to bollworm was reduced with the application of big-boll cultivars in China. The objective of the study was to investigate the effects of boll size on the contents of CryIA insecticidal protein in boll shell and cotton seed during the course of boll development. Two experiments were conducted at the Yangzhou University Farm, Yangzhou, China. In 2004, three cultivars including Sikang 1 (small-boll), Xiangza 3 (medium-boll) and Kemian 3 (big-boll) were compared for boll shell volume and 100-seed weight from 10 to 40 days after flowering (DAF), and insecticidal protein contents in boll shell and cotton seed from 10 to 50 DAF. As expected, the differences between cultivars were significant for all the four characteristics. Cultivars with bigger boll shell volume had higher 100-seed weight but lower insecticidal protein contents in both of the boll shell and cotton seed. The correlation between boll size and boll insecticidal protein content was negative (−0.653). The correlation between 100-seed weight and cotton seed insecticidal protein content was significantly negative (−0.645). In 2005, leaf cut (LC) and square removal (SR) treatments were applied to Sikang 1 and Sikang 3. The boll shell volume and 100-seed weight were decreased by LR, but increased by SR. LC significantly enhanced and SR significantly reduced the insecticidal protein contents of boll shell and cotton seed. The correlation between boll size and boll insecticidal protein content (−0.870) and the correlation between 100-seed weight and cotton seed insecticidal protein content were both highly significant and negative (−0.841). Therefore, the results of the study indicated that the boll insecticidal protein content was significantly affected by boll size. The implications of the observed results in breeding, cultural practices and pest management were discussed.     

Particle size heterogeneity in milled barley and sorghum grains: Effects on physico-chemical properties and starch digestibility

The average particle size of ground grains is known to influence properties related to processing (e.g. water absorption and solubility) and nutritional value (e.g. starch digestion rate) of human foods and animal feeds. The purpose of this study was to identify the contributions made by individual size fractions of hammer-milled barley and sorghum grains to average bulk compositional, hydration, rheological, and enzyme susceptibility properties. Barley and sorghum grains were each hammer-milled through a 4 mm screen and subsequently fractionated on a set of eight sieves ranging from 0.125 mm to 2.8 mm. Individual fractions were characterised for (1) starch, aNDF, and water content, (2) water absorption index (WAI) and water solubility index (WSI), (3) viscosity profile during cooking and cooling in excess water, and (4) in vitro starch digestibility. Weighted average values based on fraction yields and property values for WAI, WSI, and starch digestibility were not significantly different from values obtained for non-fractionated ground grains of both barley and sorghum. Glucose yields from starch digestion varied about ten-fold between the smallest and largest particle fractions, and WAI and WSI had value ranges of 1.9–2.8 g/g (sorghum), 2.1–4.0 g/g (barley) and 1.3–4.5% (sorghum), 0.7–10.3% (barley), respectively. Viscosity profiles for milled sorghum grain fractions were dominated by starch swelling which became increasingly restricted as particle sizes increased. Viscosity profiles for milled barley grain fractions did not exhibit typical starch-based behaviour and were most likely dominated by soluble fibres. Taken together, the results show that there is considerable potential for designing combinations of hydration, rheological and digestibility properties of ground grains through informed selection of appropriate grains and particle size distributions.     

多环境下大豆子粒大小性状的全基因组关联分析

为探究多环境下大豆子粒大小性状的分子遗传基础,挖掘与子粒大小性状相关的SNP位点和候选基因,利用150份大豆种质资源在2019年和2020年6个环境条件下对大豆子粒粒长、粒宽、粒厚和百粒重性状进行表型测定,并进行全基因组关联分析。结果表明：在CMLM（压缩混合线性）模型下,在6个环境条件下检测到896个与子粒大小性状显著关联的SNP位点,分布于20条染色体。不同性状检测到72个重叠的SNP位点。检测到39个稳定遗传的SNP位点,贡献率为10.68%~24.93%。通过稳定性与重叠性分析,获得35个稳定表达的SNP位点,贡献率为10.92%~23.16%。在粒宽、粒厚及百粒重性状中同时检测到显著关联的SNP位点最多,位点rs16533609的贡献率最高（16.51%）。根据稳定表达的SNP筛选候选基因,推测Glyma.03G006600、Glyma.04G077100、Glyma.08G203600、Glyma.12G195400、Glyma.17G039800、Glyma.18G202100和Glyma.20G215700等7个基因对大豆子粒大小性状有调控作用。     

旱地油用亚麻优化施肥的研究

通过５年多点氮磷肥料田间试验,对内蒙古自治区干旱、半干旱区旱地油用亚麻合理施肥进行了研究。提出了根据基础产量进行土壤肥力分级的氮磷肥料效应回归模式及最佳施肥量。在此基础上进一步探讨了不同年度降水量与肥料效应的关系,结果表明,年度降水量是影响产量和施肥肥效的主要因素,是确定旱地施肥配方的重要依据。为此,提出了以基础产量划分土壤肥力等级,同时考虑年度降水量的旱地油用亚麻氮磷肥料推荐施肥量,为无灌溉旱作地区油用亚麻合理施肥提供了科学依据。     

Effect of endosperm starch granule size distribution on milling yield in hard wheat

Increased flour yield in hard wheat is associated with increased endosperm rheology index, calculated from strength and stiffness as measured by the SKCS. A study of the fractured endosperm of hard wheat varieties grouped according to similar rheology index values was performed using environmental scanning electron microscopy (ESEM). Differing microstructures and fracture patterns were observed between each group. Specifically, the group representing high rheology index had a greater concentration of small starch granules in prismatic cells. Samples of diverse wheat germplasm were grown at two sites and subjected to laboratory milling. Starch granule size distribution (SGSD) analysis using a laser diffraction method was undertaken on a subset of samples in triplicate representing a range in flour yield. The results supported an hypothesis for a significant influence of SGSD on flour yield of hard wheat varieties. In addition, a significant part (R²>0.40 (p<0.05) at two sites) of the association appeared to be under genetic control. Results indicate a more even gradation of distributions involving an increase in the sample volume % of small granule (types B and C) and decrease in type A granules. This was associated with increased rheology index values and higher flour yield. The ratio of type A:C starch granules accounted for up to 58% (p<0.05) of the variation in flour yield in the samples studied. Thus, rheological parameters measured using a rapid SKCS screening method can be linked to the genetic regulation of SGSD with implications for the improvement of commercial processing performance of hard wheat.     

福建田埂豆地方品种资源研究 Ⅰ．地方品种主要特征特性及其分类

对280份福建省田埂豆地方品种的植物学特征特性进行了研究，依种皮色、生育期类型、籽粒大小等主要性状进行植物学分类，并制定了品种分类检索表。从280份田埂豆地方品种中随机抽取不同种皮颜色的品种140份，对株高、结荚高度、茎粗、主茎节数、分枝数、单株荚数、粒数、百粒重和单株重量等9个性状进行聚类分析，结果表明140份品种可分为5大类。     

施氮对宁杂1号油菜各枝序角果性状的调控

通过不同施N量处理,研究了N素营养对油菜各枝序角果质量的影响,结果表明：(1)油菜各枝序的角果数以主序和中上部分枝较多,并随施N量的增加而明显增加,过多地施用N肥会造成结角层角果过多而严重影响其它产量因素。(2)每角粒数以主序和中上部分枝较多,下部分枝较少。各枝序的千粒重和单位角果皮面积生产力(PPA)以主序最高,上部分枝较高,下部分枝较低。(3)适量施N可使上部8个分枝的每角粒数、千粒重和PPA都维持较高的水平。