Percentage Of Damaged Seeds Research Articles

Design and Testing of Water Jet-Based Fresh Lotus Seed Peeling Machine

Highlights Lotus seed coats are often peeled using water jets, which has not been studied in-depth. A water jet-based lotus seed peeling system is proposed and investigated in detail. Response surface method experiment was used to enhance peeling-machine performance. Proposed system performs well in terms of cost, stability, and percentage of seed peeled and damaged. Abstract. Lotus seed coats are often peeled using water jets. However, currently, existing fresh lotus seed peeling machines could process lotus seeds only if their size differences are small. Due to a lack of research on water jet operation parameters, the peeling process is often associated with a low percentage of seed peeled (PSP) and a high percentage of seed damage (PSD). A new type of water jet-based fresh lotus seed peeling machine was designed and tested to solve the aforementioned problems. Three-factor, three-level response surface method (RSM) was used in experiments to enhance peeling-machine performance, and quadratic polynomial regression equations were obtained via analysis of the experimental data. Results show that these independent variables had significant effects on PSP and PSD: water jet pressure (X1), water jet angle (X2), and processing speed (X3). Specifically, X1 and X2 had an interactive effect on PSD, whereas X1 and X3 both had a strong interactive effect on PSP and PSD. The optimal parameters were a water jet pressure of 0.60 MPa, water jet angle of 20°, and processing speed of 62 rpm, leading to predicted PSP and PSD of 93.13% and 1.65%, respectively (similar to the validation experimental PSP and PSD of 93.89% and 1.76%, respectively); thus, proving the accuracy of the RSM model. In general, the proposed peeling machine provided a high machine capacity (19.65 kg/h), a high percentage of seed peeled, and a low percentage of seed damaged, and all performance indices fulfilled the requirements for use. Keywords: Lotus seed, Parameter optimization, Peeling, Water jet.

Determination of the design parameters of the beet planter for uniform seed distribution

In the Tambov region, due to the widespread introduction of promising technologies for growing sugar beets, its yield has significantly increased, at the same time, the used seeding machines are not always able to provide the required depth of planting seeds, which leads to loss of yield and difficulty in applying fertilizers. In the course of previous studies, it was determined that with an increase in the angle of the scraper over 60 degrees, an increase in the percentage of filling the cells of the disc with seeds in various hybrids occurs, so research has established that in the hybrid PMC-120 at an angle of installation of the scraper of 70 degrees, 100 percent of the cells are filled with seeds, while in hybrids XM-1820 and Troika, the cells were filled only by 93.3%. It should also be noted that the PMC-120 hybrid with a scraper angle of 70 degrees had the lowest damage to the pellets - 0.67%, while the XM-1820 and Troika hybrids had 0.83 and 0.73%, respectively. With an increase in the angle of installation of the scraper over 80 degrees, the percentage of damaged seeds increased from 0.4 to 0.66%, on the basis of this, the design of the seeding device was proposed and theoretically substantiated, a feature of which is the reverse rotation of the seeding disc, while the rear wall of the opener is made in the form of a parabola appropriate trajectory of movement of seeds, which ensures their distribution in the immediate vicinity of its rear wall, thereby reducing the risk of falling asleep to the bed of the furrow before the granules get there. It has been determined that the trajectory of the granule movement directly depends on the angular speed of the seeding disc, which in turn depends on the geometric characteristics of the cells of the seeding disc. It is theoretically substantiated that the speed of the seed in the disc cell is determined by the sum of the projections, which makes it possible to calculate the curved surface of the opener.

Potential Factors behind the Decline of Pinus pinea Nut Production in Mediterranean Pine Forests

Mediterranean stone pine nut is appreciated for its high economic and nutritional value. Starting in 2012, Pinus pinea nut production declined throughout the Mediterranean area. The dry cone syndrome associated with this decline and the introduction of Leptoglossus occidentalis occurred simultaneously. This study aims to evaluate potential reasons behind the decline in pine nut production in Lebanon, considering climatic factors and the invasion of L. occidentalis. Correlation analysis was used to examine a potential relationship between cone yield and the percentage of damaged seeds per cone. Climatic variables were also tested. Two time periods were considered for analysis: before and after 2012. Cone production and the percentage of damaged seeds were negatively correlated (r = −0.42). From 2012 to 2017, cone production declined by 50% and the percentage of damaged seeds increased on average from 3% in 2012 up to 60% in 2017. Correlations were detected between cone production and the temperature of the hottest three months of the year of harvesting, and between cone production and average temperatures during the year of cone initiation. A conjunction of factors that include L. occidentalis and climatic factors might have affected the pine nut production in Lebanon.

Genetic analysis of seed resistance to Callosobruchus chinensis and Callosobruchus maculatus in cowpea

Callosobruchus chinensis (azuki bean weevil) and Callosobruchus maculatus (cowpea weevil) are the most destructive pests that cause significant losses to cowpea (Vigna unguiculata) seeds during storage. Development of cultivar(s) resistance to bruchids is a major goal in cowpea breeding program. Cowpea accession “TVu 2027” has been identified as moderately resistant to C. maculatus. Genetic studies of the seed resistance in this accession using strains of C. maculatus from Africa and America have demonstrated that the resistance is controlled by one or two recessive genes. However, there is no reports on genetics of the resistance to C. chinensis and to strain(s) of C. maculatus from Asia. Therefore, the objective of this study was to investigate genetics of the resistance to C. chinensis and C. maculatus in TVu 2027. TVu 2027 (P2) and PK2015VTN001 (P1; susceptible cowpea) were used to develop six basic generations (populations), viz. P1, P2, F1 (P1 × P2), F2 (P1 × P2), BC1P1 (P1 × F1) and BC1P2 (P2 × F1). The population were evaluated for percentage of damaged seeds (PDS) and area under the disease progress stairs (AUDPS; indicating infestation severity) by C. chinensis and C. maculatus. The results showed that TVu 2027 was moderately resistant to both bruchid species. Broad-sense heritability for PDS and AUDPS was moderate, being 70% and 73% for C. chinensis, respectively, and 64% and 61% for C. maculatus, respectively. Number of genes controlling C. chinensis resistance and C. maculatus resistance was two genes and one gene, respectively. Generation mean analysis revealed that genes with additive effect and additive × dominance gene interaction are involved in the resistance to both bruchid species. Correlation analysis suggested that the genes controlling resistance to C. chinensis and those conferring resistance to C. maculatus are unlinked.

Development of an SNP-based high-density linkage map and QTL analysis for bruchid (Callosobruchus maculatus F.) resistance in black gram (Vigna mungo (L.) Hepper)

Black gram (Vigna mungo var. mungo) is an important pulse crop in Asia. The cowpea weevil (Callosobruchus maculatus) is a stored-seed insect pest (seed weevil/bruchid) that causes serious postharvest losses in pulse crops, including black gram. In this study, we constructed a high-density linkage map for black gram and identified quantitative trait loci (QTLs) for C. maculatus resistance. A recombinant inbred line (RIL) population of 150 lines from a cross between BC48 [cultivated black gram (var. mungo); bruchid-susceptible] and TC2210 [wild black gram (var. silvestris); bruchid-resistant] were used to construct a linkage map of 3,675 SNP markers from specific-locus amplified fragment sequencing. The map comprised 11 linkage groups spanning 1,588.7 cM with an average distance between adjacent markers of 0.57 cM. Seeds of the RIL population grown in 2016 and 2017 were evaluated for C. maculatus resistance through two traits; the percentage of damaged seeds (PDS) and infestation severity progress (AUDPS). Inclusive composite interval mapping identified three QTLs each for PDS and AUDPS. Two QTLs, qVmunBr6.1 and qVmunBr6.2, mapped about 10 cM apart on linkage group 6 were common between PDS and AUDPS. Comparative genome analysis revealed that qVmunBr6.1 and qVmunBr6.2 are new loci for C. maculatus resistance in Vigna species and that genes encoding a lectin receptor kinase and chitinase are candidates for qVmunBr6.2. The high-density linkage map constructed and QTLs for bruchid resistance identified in this study will be useful for molecular breeding of black gram.

Identification of QTL underlying the resistance of soybean to pod borer, Leguminivora glycinivorella (Mats.) obraztsov, and correlations with plant, pod and seed traits

Soybean (Glycine max L. Merr.) pod borer (Leguminivora glycinivorella (Mats.) Obraztsov) (SPB) results in severe loss in soybean yield and quality in certain regions of the world, especially in Northeastern China, Japan and Russia. The aim here was to evaluate the inheritance of pod borer resistance and to identify quantitative trait loci (QTL) underlying SPB resistance for the acceleration of the control of this pest. Used were the 129 recombinant inbred lines (RILs) of the F5:6 derived population from ‘Dong Nong 1068’ × ‘Dong Nong 8004’ and 131 SSR markers. Correlations between the percentage of damaged seeds (PDS) by pod borer and plant, pod and seed traits that were potentially related to SPB resistance were analyzed. The results showed highly significant correlations between PDS by pod borer and plant height (PH), maturity date (MA), pod color (PC), pubescence density (PB), 100-seed weight (SW) and protein content existed. Soybeans with dwarf stem, light color of pod coat, small seeds, lower density of pubescence, early maturity and low content of protein seemed to have higher resistance to SPB. The correlated traits had potential to inhibit egg deposition and thereby to decrease the damage by SPB. Three QTL directly associated with the resistance to SPB judged by PDS at harvest were identified. qRspb-1 (Satt541–Satt253) and qRspb-2 (Satt253–Satt314) were both on linkage group (LG) H and qRspb-3 (Satt288–Satt199) on LG G. The three QTL explained 10.96, 9.73 and 11.59% of the phenotypic variation for PDS, respectively. In addition, 12 QTL that underlay 10 of 13 traits potentially related with SPB resistance were found. These QTL detected jointly provide potential for marker assisted selection to improve cultivar resistance to SPB.