Problem Of Lodging Research Articles

Unraveling Promising Genetic Variability Associated with Strong Culm and Yield Parameters in Inter Sub-Specific Cross Derived Recombinant Inbred Lines in Rice (Oryza sativa L.)

Strengthening the rice culm through genetic improvement has been an important target in breeding to abate the lodging problem in rice. The present investigation was attempted to study the variability, genetic parameters and trait association in recombinant inbred lines (RILs) derived from inter sub-specific cross of elite indica mega variety ‘Swarna’ and Tropical japonica strong culm accession ‘IRGC 39111’. Analysis of Variance (ANOVA) displayed significant variation in RILs for all the traits studied. The investigation revealed high estimates of GCV and PCV along with high heritability and genetic advance as percent of mean (GAM) for all culm strength (CS) traits revealing the role of additive gene effect and selection of these traits shall be effective in rice improvement. Correlation studies revealed that the internode breaking weight (IBW) and bending moment at breaking(M) had a high significant positive correlation with all the CS traits, panicle weight and grain yield. Thus, the direct selection of positively associated traits can improve the lodging resistance in rice. The principal component analysis (PCA) showed that, seven principal components (PCs) out of 23 traits attributed approximately 92.9% of the total cumulative variability. The traits culm thickness (CT), Internode breaking weight (IBW), section modulus (SM), bending stress (BS), Bending moment at breaking (M) contributed maximum to the total diversity and the lines with higher trait values for the aforementioned traits could be utilized as donors to improve the culm strength and its attributing traits in future breeding programs. From this study, it is evident that tropical japonica lines can be a great source of genetic diversification for rice improvement.

Determination of the Allelic Composition of the sdw1/denso (HvGA20ox2), uzu1 (HvBRI1) and ari-e (HvDep1) Genes in Spring Barley Accessions from the VIR Collection

The lodging of barley significantly limits its potential yield, leads to the deterioration of grain quality, and complicates mechanized harvesting. More than 30 dwarfness and semi-dwarfness genes and loci are known for barley, and their involvement in breeding can solve the problem of lodging. The most common dwarfing alleles are of the genes sdw1/denso (HvGA20ox2), uzu1 (HvBRI1), and ari-e (HvDep1). The aim of this study was the design of dCAPS markers for the sdw1.c and ari-e.GP alleles and the molecular screening of barley accessions from the VIR collection for identifying these and other dwarfing alleles commonly used in breeding. Two dCAPS markers have been developed to identify the sdw1.c allele of the HvGA20ox2 gene and ari-e.GP of HvDep1. These dCAPS markers and two known from the literature CAPS and dCAPS markers of the alleles sdw1.a/sdw1.e, sdw1.c, sdw1.d, and uzu1.a were used in the molecular screening of 32 height-contrasting barley accessions. This made it possible to identify the accessions with alleles sdw1.a/sdw1.e, sdw1.c, and sdw1.d of the HvGA20ox2 gene, as well as accessions with a combination of sdw1.c and uzu1.a alleles of the genes HvGA20ox2 and HvBRI1. A comparison of the results of genotyping and phenotyping showed that the presence of dwarfing alleles in all genotypes determines high or medium lodging resistance regardless of the influence of weather conditions. Twelve accessions were found to contain the new allele sdw1.ins of the HvGA20ox2 gene, which differs from the known allele sdw1.c by a larger size of PCR products. It is characterized by the Thalos_2 transposon insertion; the subsequent GTTA insertion, common with the sdw1.c allele; and by a single-nucleotide G→A substitution at the 165 position.

The Semi-dwarf Grain Sorghum (Sorghum bicolor L. Moench) Variety ‘Noeulchal’, with Increased Digestibility

Other SectionsAbstractThe sorghum (Sorghum bicolor (L.) Moench) variety ‘Noeulchal’ was developed and registered by the Department of Southern Area Crop Science, National Institute of Crop Science, in 2019. This variety was developed from the cross between ‘RTx2907’, with white grain, and ’Sodamchal’, with brown grain and semi-dwarf traits. The yield performance of ‘Noeulchal’ was 3.71 MT/ha in a local adaptability test run for two years. It had a culm length of 93 cm, which is 11 cm longer than that of ‘Sodamchal’, a panicle length of 29 cm, a culm 22 mm thick, and a panicle exsertion of 9 cm. It could reduce the lodging problem experienced with current cultivars, and is also adapted to mechanized cultivation. ‘Noeulchal’ has a waxy endosperm with 3.2% amylose and contained high levels of rapidly digestible starch. The rapidly digestible starch with gluten-free flours could contribute to the development of foods with different properties (Registration No. 9105).Keywords : Sorghum bicolor L., Semi-dwarf, Noeulchal, Waxy endosperm, Variety

Isolation of a Novel QTL, qSCM4, Associated with Strong Culm Affects Lodging Resistance and Panicle Branch Number in Rice.

Rice breeders are now developing new varieties with semi-high or even high plant height to further increase the grain yield, and the problem of lodging has re-appeared. We identified a major quantitative trait locus (QTL), qSCM4, for resistance to lodging by using an F2 segregant population and a recombinant self-incompatible line population from the cross between Shennong265 (SN265) and Lijiangxintuanheigu (LTH) after multiple years and multiple environments. Then, the residual heterozygous derived segregant population which consisted of 1781 individual plants, and the BC3F2 segregant population which consisted of 3216 individual plants, were used to shorten the physical interval of qSCM4 to 58.5 kb including 11 genes. DNA sequencing revealed the most likely candidate gene for qSCM4 was Os04g0615000, which encoded a functional protein with structural domains of serine and cysteine. There were 13 DNA sequence changes in LTH compared to SN265 in this gene, including a fragment deletion, two base changes in the 3' UTR region, six base changes in the exons, and four base changes in the introns. A near-isogenic line carrying qSCM4 showed that it improved the lodging resistance through increasing stem thickness by 25.3% and increasing stem folding resistance by 20.3%. Furthermore, it was also discovered that qSCM4 enhanced the primary branch per panicle by 16.7%, secondary branch by per panicle 9.9%, and grain number per panicle by 14.7%. All the above results will give us a valuable genetic resource for concurrently boosting culm strength and lodging resistance, and they will also provide a basis for further research on the lodging resistance mechanism of rice.

Through a Comedic Glass, Darkly: Ethics, Humor, and Home Ownership in Spain’s Early Technocratic Years (1957–1963)

The current essay analyzes three oppositional film comedies produced during Franco’s totalitarian regime, after Spain transitioned to an Opus Dei technocratic rule and after the Ministry of Housing was created to solve the chronic lodging problems of the time. My analysis focuses on how La vida por delante/ Life Ahead (Dir. Fernando Fernán Gómez, 1958), El pisito/ The Little Apartment (Dir. Marco Ferreri, 1959), and El verdugo/ The Executioner (Dir. Luis García Berlanga, 1963) humorously critique the contemporaneous housing predicaments and the existing residential legislation. The article argues that these comedies effectively breach the hegemonically sanctioned thresholds of ethical, political, and aesthetic decorum of contemporaneous Spain by successfully resorting to an eminently materialistic, antimelodramatic discourse and to unsympathetic characters, prone to successive moral capitulations in their desperate chase for a decent housing and social advancement.

Spraying Ethephon Effectively Increased Canopy Light Transmittance of Densely Planted Summer Maize, Thus Achieving Synergistic Improvement in Stalk Lodging Resistance and Grain Yield.

Increasing planting density is an effective way to improve maize yield, but high plant populations often cause a lodging problem. This experiment was conducted to investigate the effect of increasing planting density on stalk lodging resistance and grain yield, and to explore the effects on stalk and yield properties of spraying ethephon in densely planted summer maize. The summer maize hybrid, Xundan20 (XD20), was used as experimental material. It was grown by spraying water (CK) or ethephon (E) at BBCH (BASF, Bayer, Ciba-Geigy and Hoechst) 17 under three different planting densities of 60,000 plants ha−1 (L), 75,000 plants ha−1 (M) and 90,000 plants ha−1 (H) in order to explore the possibility of synergistic improvement in stalk lodging resistance and grain yield. The results from this experiment suggested that the gravity center height of densely planted summer maize was significantly increased, the stem diameter, area and number of vascular bundles were significantly decreased and the dry weight per unit internode was significantly decreased, thereby weakening the stalk rind penetration strength and bending performance, resulting in a significant increase in lodging percentage. The ear height was significantly decreased and the SPAD (soil and plant analysis development) and canopy light transmittance were increased after spraying ethephon; then, the internode dry weight per unit length was increased and the stalk rind penetration strength and bending performance were enhanced so as to significantly reduce the lodging percentage and increase the grain yield. The correlation analysis further showed that lodging percentage was significantly negatively correlated with stem diameter, area and number of vascular bundles and stalk bending performance, but there were no strong relationships with grain yield. This suggested that the synergistic improvement in stalk lodging resistance and grain yield was not contradictory. Under the experiment conditions, the effect of spraying ethephon was most significant when the planting density was 90,000 plants ha−1. At the time, the lodging percentage and grain yield were 12.2% and 11,137.5 kg ha−1, which were decreased by 44.6% and increased by 8.0% compared with the control treatment. Scientific chemical regulation could significantly improve the stalk lodging resistance and grain yield of densely planted summer maize.

Study on Adoption of Chinnor Rice Production Technology and Constraints Faced by Farmers of Balaghat District, Madhya Pradesh

The Study was conducted during 2019–20 to find out the adoption of Chinnor rice production technology by farming communities of the Balaghat district, Madhya Pradesh, India. Farmers of an area were aware about technology invented by scientists of College of Agriculture, Balaghat. Adoption of interventions involved in given technology varied from 64–100%. Majority of the respondents respond to mixing of vermi-compost and other cakes in soil (77.72%), seed rate @ 20–25 kg ha-1 (69.40%), 2–3 times of ploughing (64.51%), recommended plant spacing (75.00%), organic manures for nutrient management (88.47%), mechanical method of weed control (94.96%), try biological control insect-pest (96.33%), manual harvesting as well as bagging method of storage (98.00%). Data indicates that the lodging of the crop due to height was the major constraint in their adoption and it ranks Ist as 68.33% respondents reported the problem of lodging. Long duration required for maturity of the Chinnor than other rice varieties was another limiting factor, ranked IInd with 61.67% farmers’ response, whereas less availability and high cost of pure seed of variety ranked IIIrd with 54.33% farmers’ response. Majority of respondents (36.33%) communicate with the scientists of the college and other institutions. With some improvements in qualitative parameters of the crop, adoption by farmers and yield of the crop will increase.

Field test and evaluation on crop dividers of sugarcane chopper harvester.

In South China, the tropical weather and climate result in severe sugarcane lodging problems which greatly hinders sugarcane mechanical harvesting. The main function of the crop divider is to lift lodged canes and facilitate base-cut cane feeding. In this study, a series of field tests were conducted on crop dividers of Liugong 4GQ-180 sugarcane chopper harvester. The tests were designed to identify the relationships of the performance index (maximum lifting height of sugarcane) and the main influencing factors (machine forward speed, rotational speed of inside scrolls, and ground clearance of crop divider toes). The single factor test was conducted to determine optimum range of these test factors: the forward speed (FS) was 2.0-4.0 km/h, the rotational speed of inside scrolls (RS) was 100-140 r/min, and the toe ground clearance (GC) was 0-5 cm. The orthogonal test (three factors and three levels) was carried out to determine the optimal combination of operating parameters: FS was 2.0 km/h, RS was 115 r/min, and GC was 0 cm. In addition, the range analysis of orthogonal test results revealed that the order of each test factor affecting crop divider performance was RS, FS, GC. This study was expected to provide valuable references for the optimal operation of sugarcane harvester crop dividers. Keywords: sugarcane chopper harvester, parameter optimization, machine forward speed, rotational speed of scrolls, ground clearance, maximum lifting height, field test, evaluation, crop divider DOI: 10.25165/j.ijabe.20211401.5621 Citation: Bai J, Ma S C, Wang F L, Xing H N, Ma J Z, Hu J W. Field test and evaluation on crop dividers of sugarcane chopper harvester. Int J Agric & Biol Eng, 2021; 14(1): 118–122.

Zeolite alleviates potassium deficiency and improves lodging-related stem morphological characteristics and grain yield in rice

Zeolite is an abundant potassium (K)-rich silicate mineral that could increase K supply to plants. Potassium deficiency causes lodging problems and yield reductions in paddy fields in China. However, it is unknown whether zeolite amendments alleviate K deficiency or enhance lodging-related stem morphology characteristics in rice. A 2-year field experiment was conducted to evaluate the effect of zeolite amendment (0, 5 and 10 t ha–1) and K application (0, 30 and 60 kg ha–1) on rice grain yield, stem morphology, and K nutrient status in soil and plant tissues. In both years zeolite and K application, alone or in combination, significantly increased grain yield, mainly through increased number of panicles per plant with zeolite application and number of spikelets per panicle with K application. In the top 30 cm soil layer, zeolite amendment increased cation exchange capacity by up to 31% and available K by up to 38%. Zeolite or K application alone significantly increased stem, leaf and panicle K concentrations. Zeolite promoted K allocation to rice stems, and improved stem morphology associated with lodging index. In both years, zeolite or K application alone increased stem diameter, dry weight linear density and the breaking resistance moment by up to 7.0%, 8.3% and 16%, respectively, and decreased the stem lodging index by up to 6.7%. In summary, zeolite is an alternative source of K fertiliser and can alleviate K deficiency in paddy fields in China and elsewhere.

Comparative Evaluation of Transplanting and Sowing on Growth and Yield of Tef (<i>Eragrostis tef </i>(Zucc.)) at Jimma and Buno Bedele South Western Ethiopia

Field experiments were conducted for four consecutive years (2013-2016) under rain-fed conditions in South Western part of Ethiopia, to evaluate the time of transplanting and direct planting of different seed rates either in row or broadcast for improving growth and yield of tef. The experiment had two time of transplanting tef seedling (at 10 and 20 ahead of planting); five tef seed rates (5, 10, 15, 20, 25 kg ha^-1) planted in rows and two tef seed rates (5 and 25 kg ha^-1) planted in broadcasting. The experiment was designed in a randomized complete block design with three replications. Over year and locations mean results revealed that all parameters (number of tiller per plant, plant height, Panicle length, lodging percent, grain yield, aboveground biomass, straw yield and harvest index) were significantly affected by different planting methods (transplanting, row planting and broadcasting) and seed rates. Seedlings raised in nursery for 10 days ahead of planting then transplanted to plots at sowing time gave the highest number of tillers per plant, plant height, panicle length, grain yield, straw yield and above ground biomass. Whereas, the lowest seed rate 5 kg ha^-1 with both broadcasting and row planting gave the lowest grain yield, straw yield, above ground biomass and also lodging percent. Broadcast seeds at the rate of 25 kg ha^-1 gave the lowest number of tillers per plant, plant height and panicle length and gave the highest lodging percent. These results indicated as the seed rate increases the problem of lodging of tef increases. The Partial budget analysis revealed that the higher net benefit and higher marginal rate of return were obtained from drill seeds in rows of 20 cm apart at the rate of 10 kg ha^-1 and broadcast seed at rate of 25 kg ha^-1 with values of 4004% and 3351%, respectively. This is, therefore, drill seeds in rows of 20 cm apart at the rate of 10 kg ha^-1 and broadcast seed at rate of 25 kg ha^-1 can be used to high and economic yield of tef at South Western parts of Ethiopia.

Application of Plant Growth Regulators on Soft White Winter Wheat under Different Nitrogen Fertilizer Scenarios in Irrigated Fields

Lodging in cereal crops can result in yield loss and harvesting difficulties for growers. Application of plant growth regulator (PGR) has been an indispensable management practice to reduce lodging problems that are often exacerbated during high wind growing conditions and/or high nitrogen (N)/water environments, but the data is limited in the Columbia Basin of Oregon. The objective of this research was to evaluate the effect of two PGR products (chlormequat chloride-CC, trinexapac-ethyl-TE) at different rates and application timings on two soft white winter wheat varieties (ORCH-102 and SY Ovation). Crop growth (stem height and thickness), yield-related (spike density as ears m−2, seeds per spike, grain weight) and quality parameters (test weight, protein) were measured for two cropping seasons from October 2017 to July 2019 following the application of the two PGR products at tillering (GS21-26), stem elongation (GS30-32), and/or flag leaf (GS37-39) stages under a high-N fertilizer scenario. In both growing seasons, no lodging problems were recorded for any treatments. The plant height was reduced after PGR application, but the impact on stem thickness was limited. PGR application slightly affected wheat yield, yield components, testing weight, and protein level in both growing seasons. Our results suggested that the effect of PGR application is relatively limited if no lodging problem occurred.

Amelioration of lodging in barley (Hordeum vulgare) using plant growth regulators

The present study with aim to evaluate the efficacy of plant growth retardants to enhance productivity of barley by reducing lodging behaviour under high nitrogen supply was carried during rabi 2016–17 and 2017–18 at Rajasthan Agricultural Research Institute, Durgapura, Jaipur. Results revealed that application of 125% and 150% RDN recorded significantly higher periodic plant height and dry matter accumulation over 100% RDN. The combined application of Chlormequat Chloride fb Cerone reduced the plant height by 6.65, 4.49 and 2.93% at 60 DAS, 12.19, 8.58 and 3.57% at 90 DAS and 11.46, 8.50 and 4.63% at harvest, thus, reduced the lodging score by 70.05, 52.01 and 29.40% over water spray, CCC and Cerone, respectively. The significantly maximum lodging score (10.23), number of effective tillers/m2 (318.69), spike length (12.03 cm) and number of grains/spike (44.67) were registered with 150% RDN. The combined spray of Chlormequat Chloride fb Cerone increased the effective tillers by 14.97, 10.12 and 5.11% and test weight by 8.90, 5.72 and 2.88% over water spray, Chlormequat Chloride and Cerone used alone, respectively. The grain, straw and biological yield of wheat with 150% RDN were 10.98, 5.17 and 7.90% higher compared to 100% RDN, respectively. However, 125% RDN was found statistically at par with 150% RDN. The application of 125 and 150% RDN increased the gross return by 5.72–9.48% and net returns by 7.47–12.02% and B:C ratio by 5.74- 8.66% over 100% RDN. The combined application of CCC fb Cerone increased gross by 9.65, 6.01 and 2.37% and net returns by 10.31, 7.98 and 2.70% over water spray, Chlormequat Chloride and Cerone used alone, respectively. Therefore, it can be concluded that use of plant growth regulators i.e. Chlormequat Chloride fb Cerone under higher use nitrogen (125% RDN) can be advocated as sustainable strategy to manage the problem of lodging and enhancing productivity and profitability of barley cultivation.

Application of rast electronic microscopy in cytohistological studies of flax

The article highlights the problem of lodging of flax due to adverse weather conditions. The features of the growing zone, the economic value of flax and its products are updated, as well as the damage caused by bad weather during the growing season. Flax resistance to lodging is directly related to the anatomical structure of the stem, but the authors specify that this feature is related to the structure of the submucosa (hypocotyl). The theoretical part of the article describes the flax fiber and its technological properties. Therefore, the purpose of the article was to investigate the cytisthistological structure of the transverse section of the subunit knee of stems of flax-gland by scanning electron microscopy to determine the resistance to lodging. As the object of research used varieties of Ukrainian and foreign selection: Gladiator, Merylin, Zhuravka, Kievsky 2. The weather conditions during the years of research (2016‒2018) are quite characteristic of the area of the northeast Polesie and reflect the instability of hydrothermal modes of vegetation of flax-liqueur in this zone. Testing the experimental material of these studies over three years with contrasting weather conditions allowed us to objectively evaluate the responses of flax varieties to these conditions. To perform the tasks assigned to the job laid a nursery of a comparative test. The predecessor of flax was winter wheat after many years of herbs. The main tillage was carried out according to the type of half-soil; stubble peeling, plowing to a depth of 22‒25 cm, and two cultivations as weeds germinated to a depth of 8‒10 and 5‒6 cm. Slice studies were performed using a scanning electron microscope. The article presents the results of studies of the cytologic and histological structure of stems of varieties of flax-shoots of various degrees of resistance to lodging using the method of scanning electron microscopy, presents the structure and features of sections of hypocotyl stems of plants of flax – duckweed and also the average thickness. The authors carried out 250 measurements of the thickness of the cell walls of the sections of the submucosa. It was found that in flax varieties, more resistant to lodging, cells of conductive and mechanical tissues are not deformed, unlike unstable varieties. In addition, the average cell wall thickness of resistant varieties is greater than unstable ones.

Root and shoot traits in parental, early and late generation Green Revolution wheats (Triticum spp.) under glasshouse conditions

Introduction of stem-dwarfing genes had a major impact on wheat breeding and production. It is estimated that 70–90% of modern wheats carry one or more such genes. These genes were the cornerstone of the Green Revolution. They solved the lodging problem by reducing stem height, thus allowing a marked increase in mineral fertilizer use. These genes also changed biomass allocation and allowed more carbon assimilates to be stored as grain. With heavy fertilization and irrigation, plants had little use for an extensive and expensive root system for uptake of water and nutrients. However, with climate change and limited water and nutrient sources, there is a need to remodel crops with novel genetic variation available in landraces and old varieties. In this study, we evaluated nine accessions of wheat representing gene pools of parental, early-tall and late-semi-dwarf Green Revolution wheats for root and shoot biomass and grain yield under well-watered conditions in a glasshouse. Significant genotypic variation was found for total root biomass and root distribution in the soil profile as well as for plant height and days to anthesis. Modern wheats have reduced root-system size relative to their predecessors. This may be the effect of the dwarfing genes or an indirect effect of negative selection pressure, but the wheat root system became smaller within the last century.

A Review of a Half Century Hybrid Maize Breeding Experiences with Combined Tolerance to Major Biotic and Abiotic Stresses in China and Other Developing Countries

Genetic vulnerabilities (GV) of maize (Zeamays L.) have been experienced for a half century globally. Research on quantitative gene resistance (here called “co-survival tolerance”) against GV have been studied on Puccinia sorghi common rust, Exserohilum turicum northern corn leaf blight, Bipolaris maydis Southern corn leaf blight, maize streak virus, parasitic witchweed Striga species, Puccinia polysora tropical rust, Peronosclerspora sorghi downy mildew and Ustilago maydis smut. Among the above GE experiences, the most striking experience was parasitic witchweed Striga hermonthica, S. asiatica and S. aspera species in Africa. Without co-survival tolerance, Striga problems in Africa may not be solved in next few decades. The tolerance is controlled by quantitative gene. African origin parasite problems are causing damage of Africa’s food crops in 7 billion US dollars annually. Parasites and hosts must be live together and co-survive in nature. The author’s experiences of GV with maize in China have been two popular hybrids; Jeungdan 958 and Seunok 335. The former hybrid was covered over 10 million ha during the period of 2007-2013. Its genetic vulnerability due to too wide areas of cultivation of a single hybrid was occurred by corn borers and smut. While Seunok 335 and its sister hybrids now cover majority of maize cultivation of North Eastern (NE) region of China. Seunok 335 has severe root lodging problem under storm. The author observed the lodging in the north of Shenyang, Liaoning Province in 2008, followed in the NE provinces. In addition, it was attacked by E. turcicum in the western region of Jilin Province. Both USA and China have a quarter of the world maize cultivation, each 35 million ha and produce average yield of 10.5 and 6.5t/ha, respectively. To increase maize production for feed, food and industries as well as to reduce climate changes, China’s maize cultivation and breeding must be focused on diverse hybrid development and machine harvest. The later returns stalk and leave to soil. Copies of super hybrids e.g. Seunok 335 by other companies must be discouraged. Under climate changes, breeding stable hybrids with tolerance controlled by QTL must be encouraged. Tolerance breeding has clear advantage from GMO because it shall provide a buffering effect minimizing mutation of aggressive genes. Under the climate changes, the tolerance breeding confers buffering effects of host stability. The author has bred hybrids with tolerance against major biotic and abiotic stresses. Target traits are normal field, sticky, sweet maize, bio energy maize with genes of bm3 + high sugar + leafy, and black herb maize.

Evaluation of Hybrid and OPV Maize Varieties for Grain Yield and Agronomic Attributes under Farmer's Field Conditions at Dukuchhap

Field experiments were conducted during two consecutive years 2006 and 2007 in full season of maize (May-Sep) at Dukuchhap, Lalitpur to find out impact of growing hybrid and OPV maize in different rows combinations with respect to their pure stands in same environment of growing and to sort out non-lodging maize varieties. The experiments consisted of an open pollinated variety (OPV) 'Deuti' and hybrid 'Gaurab' in different row combinations (50% hybrid + 50% OPV, 75% hybrid + 25% OPV, 75% OPV + 25% hybrid plus their pure stands). The results showed that Gaurab (yellow, flint type) and Deuti (white, semi- flint type, selected from CIMMYT's material ZM 621) did not vary significantly in grain yield and yield components. There was no effect of mixed row culture between the OPV and hybrid for grain yield and yield attributes. A bivariate correlation coefficient between agronomic traits and ear traits indicated that there was a positive relation among these traits. However, a positive and highly significant (r = 0.766**) relationship between ear fill and ear length was observed while a very weak relation (r = 0.096*) between grain weight/ear and ear height was also noticed suggesting taller the ear height lower the grain yield/ear and vice versa. The findings of the study support that plant height and ear height were weakly related with other ear traits; nevertheless, these were highly related to grain weight/per plant. To cope with stalk lodging problem and to attain higher grain yield these varieties are equally potential and recommended to grow under Dukuchhap conditions.Nepal Agric. Res. J. Vol. 9, 2009, pp. 17-20 DOI: http://dx.doi.org/10.3126/narj.v9i0.11637

Evaluation of grain density, yield and agronomic characters in some selected rice (Oryza sativa L.) genotypes

Correction : Due to an error in the formatting of this paper, the incorrect Introduction was included in the PDF. On 1 September 2015, the Introduction to this paper was replaced with the correct version. Our apologies to the authors of the paper for this error – Editors.Rice (Oryza sativa L.) is the most important food crop of the developing world and belongs to family Poaceae (Graminae). This experiment was conducted at Regional Rice Research and Development center, Bombuwala with the objective of evaluating grain density, yield and agronomic characters of some selected rice genotypes with five new breeding lines and five improved varieties. The new breeding lines 09-892, 09-897, 03-1198, 09-1054-1, 09-1063-3 and the improved varieties Bg 358, Bg 359, Bw 363, Bw 364 and At 362 were cultivated in randomized complete block design with three replicates. After land preparation, the field layout was prepared and then the seeds were broadcasted. Observations of yield and agronomic characters were taken at their corresponding stages of the plant. The variety Bw 364 and 09-1063-3 new breeding line had significantly long culm length and panicle length than other varieties. But 09-892 breeding line with intermediate culm showed a lodging problem in the field. New breeding line of 09-1054-1 showed early flowering than other varieties and it deviated from 3½ month aged group flowering. New breeding line of 09-892, 09-897 and 09-1054-1 took shorter time for maturity. The variety Bw 364 (2.6 g) had significantly higher hundred seed weight than other varieties. Numbers of spikelets/panicle did not vary significantly with treatments in the experiment. The variety At 362 (16.3%) and the new breeding lines 09-897 (25.6%), 03-1198 (26.3%) had the lowest spikelet sterility percentage and Bw 363 (40%) showed the highest spikelet sterility percentage in the trial. High density grain percentage significantly varied among the tested genotypes ranging from 45 to 68%. The highest high density grain percentage was shown by Bg 358, Bg 359, Bw 364, At 362,09-892,09-897 while 03-1198 and 09-1054-1 had the lowest high density grain percentage. Among the improved varieties, Bw 364 (5.3 t/ha) and At 362 (5.1 t/ha) showed the highest yield in the trial whereas the new breeding lines 03-1198 (4.1 t/ha) showed the highest yield. Hence, 03- 1198 new breeding line can be selected for adaptability tests and it promises to proceed in the varietal selection programme to become a recommended variety.Journal of the University of Ruhuna 2013 1(2): 19-22

PLANT-DERIVED AEROSOL-SMOKE AND SMOKE SOLUTIONS INFLUENCE AGRONOMIC PERFORMANCE OF A TRADITIONAL CEREAL CROP, TEF

SUMMARYThe positive role of plant-derived smoke on seed germination and post-germination processes is well documented. The present study examined if plant-derived smoke with various methods of application influence the agronomic performance of a traditional cereal crop, tef [Eragrostis tef (Zucc.) Trotter]. Comparisons were made in potted tef plants, which germinated from seeds treated with smoke-water (1:500 dilution), Karrikinolide1 (KAR1, 10−8 M) solutions and seeds pretreated with cool aerosol-smoke for 10 min (rinsed and unrinsed afterwards). The smoke-related treatments modified a number of physiological, morphological and agronomic features of Eragrostis tef. Compared with the control, KAR1 and aerosol-smoke treatment of the seeds significantly improved plant height. All the smoke-related treatments significantly promoted stem-thickness whereas number of tillers and grain and dry biomass responded positively to aerosol-smoke and smoke-water treatments. These findings indicate that the plant-derived smoke treatment has a great potential to improve grain and dry biomass yields of tef. Moreover, due to its positive role in improving stem-thickness, smoke treatment may assist in combating lodging problems in cereals such as rice, wheat and barley, provided they are responsive to smoke treatments.

Evaluation of rice hybrids in varying environments

Rice varieties cultivated in coastal areas of India are highly season-specific. Most of them are suitable either for wet (WS) or dry seasons (DS), but a few are suitable for both seasons. Nitrogen fertilization in WS is limited by the problem of lodging caused by frequent rains or storms. Commercial exploitation of heterosis depends on identification of hybrids adapted to variable weather and N levels. Thirty rice hybrids were evaluated in five environments at two N levels in DS, 60 and 120 N (E1, E2) and three in WS, 30, 60, and 120 N (E3, E4, and E5) (see table). They were derived from five CMS lines (IR46830A, IR54752A, IR54754A, IR58025A, and IR62829A) and six restorer lines (WGL3962, Swarna, Vajram, Pratibha, IR36, and IR64). The trial was carried out under an irrigated system at the ARS.

Gibberellin Biosynthesis Inhibitors Help Control Plant Height for Improving Lodging Resistance in E. Tef (Eragrostis tef)

Eragrostis tef, a tall stature and highly nutritious cereal grown in East Africa, has a serious lodging problem that reduces its productivity considerably. Certain plant-growth regulators are known to restrict growth and consequently improve lodging resistance in cereals by affecting gibberellin biosynthesis. The effect on height of growth regulator chlormequat chloride (CCC) was determined for varieties Gea Lammie with a short phenotype and DZ-01-196 with a tall phenotype. Chlormequat chloride decreased plant height by 27% in Gea Lammie and by 46% in DZ-01-196. More detailed analysis of growth regulator application by including Paclobutrazol (PBZ) on the tall tef variety DZ-01-196 revealed that both CCC and PBZ reduced culm length, but had no effect on internode diameter. Chlormequat chloride at 100 mM especially reduced the length of the lowermost internodes. Treatment with CCC on the other hand did not increase panicle-bearing tillers, but grain yield in CCC-treated plants was comparable to non-treated control. The regulation of gibberellin biosynthesis could therefore be a key target for improving lodging resistance in Eragrostis tef.