Cob Girth Research Articles

Effect of nano ZnO on growth and yield of sweet corn under South Gujarat condition

A field experiment was conducted at College Farm of Navsari Agricultural University, Navsari to study the impacts of ZnO nanoparticles on growth and yield of sweet corn. Total twelve treatment of bulk ZnO, ZnSO4 and ZnO nanoparticles (ZnO-NPs) were taken as seed treatment and foliar application during experimentation. Among different treatments, foliar application ZnO-NPs (M3) @ 500 ppm gave significantly higher growth attributes viz. plant height at 60 DAS (173.67 cm) and harvest (198.85 cm), and yield attributes viz. number of cob per plant (1.73), cob length (30.13 cm) and cob girth (19.66 cm) as well as cob yield (18.98 t/ha) and straw yield (7.12 t/ha) of sweet corn.

Kwanu Local – A High Yielding Traditional Maize Cultivar of Jaunsar Tribal Region of Uttarakhand and a Promising Genetic Resource for Maize Improvement

Globally maize is the second most important crop in terms of acreage where as in India it ranks third after wheat and rice. Maize productivity has been breaking unprecedented barriers owing chiefly to wide scale cultivation of high yielding hybrids. Sustaining high yields of hybrids necessitates continued efforts for creation of novel gene assemblages and/or discovery of such naturally existing constellations. Traditional local cultivars are an important source of the latter. Kwanu Local is an example of such a traditional cultivar that contributes significantly towards sustaining food, fodder and fuel requirement of Jaunsari tribal community of Kwanu cluster in Dehradun district of Uttarakhand. It is a tall, high yielding, medium duration, semi-dent yellow bold-grained cultivar and owes its characteristic present form to multiple infusions from diverse populations that have taken place over the long history of its cultivation in the region. Its cultivation over a vast contiguous expanse and the selection practices followed by the farming community ensure maintenance of high heterozygosity in the population, assuring sustained high yields. The cultivar possesses many desirable features that make it a potential genetic resource for a variety of traits of agronomic importance (cob length, cob girth, number of kernels/row and kernel size). Its use for increasing kernel size has been well demonstrated. Kernel size in the backcross progenies involving inbreds VQL 1 (255 g) and V 400 (215 g) as recipients and Kwanu Local (343 g) as donor exhibited kernel size range of 260-293 g (VQL 1 x Kwanu Local) and 228-245 g (V 400 x Kwanu Local), showing increase of 6-14 and 2-15%, respectively, in the two crosses. With its local adaptability and high yield coupled with other desirable traits, Kwanu Local holds potential as a promising genetic resource for maize improvement.

Effect of high planting densities and cultivars on productivity of rainfed maize (Zea mays)

An experiment was conducted at research farm of Advanced Centre of Rainfed Agriculture (ACRA), Rakh Dhiansar SKUAST-Jammu, using factorial randomized block design (FRBD) with three replications to study the effect of planting densities on plant growth and productivity of maize varieties. The experiment consisted of two maize varieties, viz. Double dekalb and Mansar and six plant spacings of 40 × 15, 40 × 20, 50 × 15, 50 × 20, 60 × 15 and 60 cm × 20 cm. Varieties and planting density had a significant effect on plant height, dry matter accumulation, leaf area index (LAI) and yield attributes like cob length, cob girth, number of grain row/cob, number of grains/cob row, number of grains/cob, grain and stover yield. The variety Double dekalb attained significantly higher growth and yield attributing parameter values and grain/stover yield. Spacing of 50 cm × 20 cm observed significantly higher values of grain yield and yield attributing characters. However, 40 cm × 15 cm spacing achieved significantly higher values of plant height, dry matter accumulation, LAI and stover yields. Also the spacing of 50 cm × 20 cm exhibited statistically higher values of N, P and K uptake while 40 cm × 15 cm spacing recorded significantly lowest values of nutrient uptake. Among the varieties Double dekalb exhibited higher values of net returns and B:C ratio values while among the different spacing’s, 50 cm × 20 cm registered the highest net returns and B:C ratio values.

Evaluation of maize (Zea mays) cultivars under organic production system in north-western Indo-Gangetic Plains of India

Increased awareness of environmental degradation and growing concern of human health has attracted worldwide attention towards organic farming. A field experiment was carried out during kharif of 2013–2014 to identify suitable maize (Zea mays L.) cultivars having high yield potential under organic production system. Twelve released cultivars of maize varied in duration and nitrogen requirement were evaluated. Results revealed that late maturing cultivars PMH-1 and PMH-3 being at par to each other recorded the significantly higher values of growth parameters like plant height, dry matter accumulation and leaf area index; and yield attributes in terms of cobs plant, cob length, cob girth, grain rows/cob, grains/row and test weight, whereas the extra early cultivars like Vivek QPM-9 being at par with Vivek Hybrid-9 registered the lowest values of growth and yield attributes. The late maturing cultivars like PMH-1, PMH-3, Seed tech-2324 and Bio-9681 produced significantly higher grain yield (>5.0 t/ha) and biological yield (>12.5 t/ha). Cultivars PMH-4 among medium maturity group produced comparable yield with late cultivars. Grain yield across the varied duration cultivars had a significant positive correlation with cob length, grains/row and N uptake. As per their maturity class, the extra early and early cultivars commence silking (<50 days) and physiological maturity (<82 days) significantly earlier than medium and late cultivars. Moreover, extra early cultivars (Vivek Hybrid-9 and Vivek QPM-9) recorded significantly higher protein content in grain amongst the cultivars tested. The late cultivars PMH-1 and PMH-3 being at par with each other recorded the highest N, P and K uptake in plants while lowest nutrient uptake was observed in the extra early Vivek QPM-9 and Vivek Hybrid-9. Late cultivar PMH-3 followed by PMH-1 recorded the highest net returns (` 66,759) and B:C ratio (1.79) of organic maize cultivation. Soil fertility status in terms of organic carbon, available P and K could not be influenced significantly, however the available N content was significantly higher under extra early cultivars Vivek QPM-9 (172.1 kg/ha) and Vivek Hybrid-9 (170.3 kg/ha). Thus, it can be concluded that PMH-1 and PMH-3 cultivars of maize are most suitable for growing in north-western plains region of Uttar Pradesh under organic production system.

Study on per se performance and heterosis for kernel yield and its attributing traits in maize [Zea mays (L.)

The phenomenon of heterosis has provided the most important genetic tools in improving yield of crop plants. Identification of specific parental combination capable of producing the highest level of heterotic effects in F1 has immense value for commercial exploitation of heterosis. The experimental material comprised of eight parental lines, 28 F1 hybrids with one standard check (GAYMH-1). On the basis of per se values, the parents CML 338, VL-1032 and BLD-11 were recorded maximum kernel yield per plant, while in case of hybrids, CBE-98 × BLD-11, CBE-98 × MRCN-3 and CBE-26 × BLD-11 were best for kernel yield per plant. The population mean for kernel yield per plant was 99.74 gm. Among the 28 hybrids, 4 hybrids i.e. CBE-26 × MRCN-3, CBE-26 × VL-109178, VL-109178 × MRCN-3 and CBE-98 × MRCN-3 manifested significant and desirable heterosis over mid parent, better parent and economic heterosis over check (GAYMH-1) for kernel yield per plant and other component traits viz.cob weight, cob length, cob girth, 100-kernel weight, number of kernel row per cob and number of kernel per row.

Association of phytic acid towards the yield attributing traits in maize (Zea Mays. L)

The current investigation was done to understand the role of phytic acid and its contribution to yield and yield attributing traits in maize. Phytic acid is an anti-nutritional factor involved in chelating phosphorus and other micronutrients in food. On contrary, it is a major regulator of the metabolic pathways in plants. This study involved the correlation and path analysis of nineteen morphological and two biochemical traits with phytic acid as the dependent factor. A significant positive correlation of seed girth, seed thickness, hundred seed weight, cob weight, starch content and single plant yield with phytic acid were observed. This elaborated the essentiality of phytic acid in seed set and pollination in maize. Consequently, this study also ensured the increase in free inorganic phosphorous content in reduced phytic acid lines through their negative association and revealed its chelating ability in foods. Further the path analysis established highest positive direct effect of single plant yield, seed girth, cob placement height, cob weight, days to 50 percent silking and cob girth towards the phytic acid content in maize. This reinforces the direct contribution of phytic acid in crop development. The correlation also encompasses the role of phytic acid in starch accumulation and seed thickness in maize by means of their positive association. Therefore, from this study it could be concluded that phytic acid has a functional relationship with the major yield contributing traits in maize. Hence proper selection criteria have to be followed for producing elite lines with low phytic acid in maize.

Genetic variability, character association and path analysis for yield and yield component traits in maize (Zea mays L.)

The present investigation was conducted to explore the genetic variability, character association and path analysis for yield and yield component traits in maize. One hundred maize inbred lines obtained from Department of millets, TNAU were raised along with five checks in Augmented block design II and observations were recorded on twenty morphological traits. Analysis of variance showed significant genotypic variance for all the characters. High PCV, GCV heritability and genetic advance as percentage of mean were recorded for anthesis silking interval, number of tassel branches, number of kernels per row, grain yield per plant, cob weight, ear height and number kernel rows per cob. This indicated the effectiveness of selection towards these traits. Critical analysis of results obtained from character association indicated that grain yield per plant had positive significant association with cob weight, cob girth, number of kernels per row plant height, cob length, ear height, 100 kernel weight, tassel length and chlorophyll index. Thus selection for these traits could bring about an improvement in yield attributes of maize. Path analysis for the attributed traits revealed the direct influence of cob girth followed by number of kernels per row, shelling percentage, days to 50 percent silking and ear height on grain yield. Hence these traits could be used as an effective selection indicator to identify the elite genotypes from a population.

Gene action and combining analysis for kernel yield and its attributing traits in maize [zea mays (l.)

Eight maize (Zea mays L.) genotypes were crossed in a half diallel mating design.The analysis of variance for combining ability revealed that mean sum of squares due to general combining ability were found significant for all the traits except cob girth, whereas, the specific combining ability effects were found highly significant for all the characters except anthesis-silking interval. The low ratio (<1.0) of GCA to SCA variance for sixteen traits indicated that non-additive type of gene action was predominant in the expression of yield and component traits. Based on estimates of general combining ability effects revealed that four parents BLD-11 (5.19), CML-338 (4.28), VL-1032 (1.68) and VL-109178 (1.25) were found good general combiners because they registered significant and positive gca effects. The estimates of sca effects revealed that 23 hybrids were exhibited significant positive sca effects. The spectrum of differences in sca effects for this trait ranged from -2.70 (CBE-98 × CML-338) to 27.57 (CBE-98 × MRCN-3) and the top most three hybrids for kernel yield per plant on the basis of specific combining ability effects were CBE-98 × MRCN-3 (27.57), CBE-98 × BLD-11 (23.16) and CBE-26 × BLD-11 (21.20).

Residual effect of organic amendments on growth, productivity, economics and agri-energetics of local popcorn (Zea mays everta) in toria (Brassica campestris) – popcorn cropping system under mid hills of Sikkim Himalayas

Under organic management condition, it is presumed that the nutrients applied to preceding crops exhibits the considerable effect on succeeding crops, hence a fixed plot field experiment was conducted during three years (2011 to 2014) at Research Farm, National Organic Farming Research Institute (NOFRI), Tadong, Gangtok to assess the residual effect of mulching and vermicompost on growth, productivity, profitability and energetics of popcorn (Zea mays everta) under toria (Brassica campestris)-popcorn cropping system. The results revealed that the mulching materials applied to the preceding crops exhibited significant residual effect on growth, yield attributes and grain yield of succeeding popcorn over non-mulching (bare soil). However, among the mulching materials, rice straw mulch @ 5 t/ha exerted maximum residual effect and resulted in higher cob length (16.0 cm), cob girth (12.0 cm), grain yield (1.93 ha), stover yield (3.07 t/ha), net returns (72.8 × 103 rs.`/ha), B:C ratio (2.87) and energy use efficiency (20.62%) of popcorn. With regards to the vermicompost levels, residual effect of vermicompost @ 1.5 t/ha recorded the maximum grain yield (1.9 t/ha), net returns (71.3× 103 rs.`/ha), B:C ratio (2.81) and energy use efficiency (20.34%) of the succeeding popcorn under toria-popcorn cropping system.

Growth, crop phenology and PAR interception in kharif maize (Zea mays L.) as influenced by planting methods and nitrogen levels

A field experiment was conducted at Punjab Agricultural University, Ludhiana during kharif 2015 to study the influence of three planting methods (flat, ridge and bed planting) and five nitrogen levels (0, 90, 120, 150 and 180 kg N/ha) on the growth, phenology and PAR interception in kharif maize. Bed planting method produced significantly higher LAI, DMA, leaf chlorophyll content, cob length, cob girth, number of rows per cob and grain yield of maize as compared to flat sowing method but was statistically at par with ridge planting method. Maximum PAR interception of 78.2% was registered at 90 DAS when the crop was raised on beds. Tasselling, silking and physiological maturity were enhanced by 2.3 to 2.5, 3.3 to 3.7 and 2.2 to 2.6 days, respectively, under bed and ridge planting methods as compared to flat sowing method. Application of 150 kg N/ha recorded significantly higher LAI, DMA, leaf chlorophyll content, PAR interception, cob length, cob girth, number of rows per cob and grain yield over 120, 90 and control but at par with 180 kg N/ha. Maximum PAR interception of 82.8% was observed with application of 180 kg N/ha at 90 DAS which was significantly higher than 0, 90 and 120 kg N/ha but was at par with 150 kg N/ha. Nitrogen application enhanced the tasselling and silking stages but delayed the physiological maturity stage.

Genetic diversity in sweet corn inbred lines (Zea mays L.)

A total of fifty inbred lines of sweet corn were evaluated for eight quantitative characters at the Millet Breeding Station, Department of Millets, Tamil Nadu Agricultural University, Coimbatore during kharif 2014 to study the genetic diversity using multivariate (D square) analysis. The fifty inbreds categorized in to ten distinct clusters. The intra-cluster distances in all the ten clusters was low, indicating that the genotypes within the same cluster were closely related. The highest inter-cluster distance was observed between cluster I and cluster X and the lowest between the cluster II and III. The cluster VII and cluster X contained the highest (24) and lowest (1) number of genotypes, respectively. Cluster VI showed the highest mean values for kernel yield and all the yield contributing traits. Cob girth and number of tassel branches expressed maximum contribution towards total divergence among different characters. Development of hybrids utilizing these genotypes has the chance to obtain higher heterosis with high performing crosses.

Genetic diversity in maize inbreds under excess soil moisture condition

Genetic diversity study was done in 64 maize inbreds grown under excess soil moisture condition.The genotypes were grouped into eight clusters. It was observed that all intercluster distances were larger than all intracluster distances. Such results indicated that genotypes included within a cluster had less diversity among themselves but wider genetic diversity among the inbreds of different clusters. The highest inter cluster distance was observed between cluster IV &amp; VII followed by IV &amp; V , IV &amp; VIII, II &amp; VII and I &amp; IV. The highest intra cluster distance was noticed in cluster V and the lowest was in cluster VII. The highest yield/plant, cob girth, number of rows/ear, number of grains/plant, SPAD value and number of nodes with brace roots were observed in cluster IV. The lowest mean value for yield/plant yield components and dwarf statured plant were observed in cluster VII. The plant height, ear height,days to 50% tasseling and silking, cob length, cob girth, 100 grain weight and SPAD value contributed considerably to total divergence. The genetically diverged genotypes in these distinct clusters could be used as parents in hybridization program for getting desirable hybrid(s).Bangladesh J. Agril. Res. 42(2): 379-385, June 2017

EFFECT OF INTERCROPPING ON YIELD OF MAIZE HYBRIDS WITH MUNGBEAN

Maize (Zea mays L.) occupied the third place mainly cereal/ fodder produce in the world. Maize gained a chief place in the many cropping pattern of Pakistan. Intercropping is economically beneficial and favorable for the fertility restoration of land. Intercropping of maize with mungbean increased water use efficiency, light use efficiency as well as nutrient use efficiency which positively affect the different yield as well as agronomic parameters like plant height, number of grain row per cob, cobs length, cob girth, thousand grain weight, total dry matter and seed yield which ultimately increases the final yield.

Growth, yield and quality of Rabi sweet corn as influenced by different spacing and fertilizer levels

A field experiment was conducted during Rabi 2011 Navsari to assess the response of Rabi sweet corn to spacing and fertilizer levels under south Gujarat condition. The experiment comprised of sixteen treatment combinations consisting four levels of plant spacing (60 x 15, 45 x 20, 30 x 30 and 60 x 30 cm ) and four fertility levels (60-30, 90-45, 120-60 and 150-75 kg N-P 2 O 5 /ha).Plant spacing of 60 x 30 cm, 45 x 20 cm and 60 x 15 cm attained significantly higher plant height compared to 30 x 30 cm. While stem diameter and number of leaves per plant were not influenced by different spacing levels. The sweet corn plants exhibited significantly maximum values of yield attributes viz., cob length, cob girth, under spacing of 45 x 20 cm. Number of cobs per plant and cob yield per plant were higher under spacing of 60 x 30 cm. The highest green cob yield was recorded at spacing of 45 x 20 cm closely followed by 30 x 30 cm. Quality parameters viz., crude protein content in cob and fodder reducing and non-reducing sugar content of grains were higher at spacing 45 x 20 cm. The growth of sweet corn in terms of plant height, number of leaves per plant, stem diameter were maximum with application of 150-75 kg N-P 2 O 5 /ha. The sweet corn plants exhibited maximum values of yield attributes viz., number of cobs per plant under 150-75 kg N-P 2 O 5 /ha and found at par with those recorded under 120-60 kg NP 2 O 5 /ha. Whereas cob length, cob were under 120-60 kg N-P 2 O 5 /ha and found at par with those recorded under 150-75 kg N-P 2 O 5 /ha. Application of 150-75 and 120-60 kg N-P 2 O 5 /ha significantly increased green cob yield over 90-45 and 60-30 kg N-P 2 O 5 /ha. Quality parameters viz., protein content of cob and fodder were significantly enhanced. Thus, from the present study, it seems quite logical to conclude that higher production and net returns from Rabi sweet corn ( var. Madhuri ) can be secured by sowing the crop at 45 cm x 20 cm spacing and fertilizing with 120-60 kg N-P 2 O 5 /ha on clayey soil under south Gujarat condition.

Combining ability analysis for yield and its component characters in maize (Zea mays L.)

Line × tester analysis was carried out involving fourty two lines and three testers in maize for assessing the combining ability for yield and its component characters. Hybrids recorded significant variance for all characters studied. Variance due to parents were significant for characters viz., days to 50% tasseling, days to 50% silking, plant height (cm), ear height (cm), cob length (cm), cob girth (cm), number of grain rows per cob, number of grains per row, number of grains per cob, 100 grain weight (gm) and grain yield per plant (gm). The variance due to sca was higher than gca indicating the predominance of non-additive type of gene action for the above mentioned traits. Among the lines, the line RML 12, was identified as the best general combiner with higher per se performance for most of the yield contributing traits followed by RML1, RML 26, RML 27 and RML 34. Considering the testers, RML 48 was found as the best general combiner with better mean performance for most of the yield contributing traits followed by RML 47. Among the crosses, RML12 x RML48 was found to be the superior with positive significant sca effects and better mean performance for grain yield, cob girth, number of grain rows per cob and no of grains per cob. Similar superior positive significant sca effects with better mean performance were also observed in RML26 x RML48 (no of grains per cob, grain yield per plant and grain yield per plot), RML27 x RML48 (grain yield per plant, grain rows per cob, grains per cob) and RML37 x RML48 (cob girth, hundred grain weight, grain yield per plant and grain yield per plot.

Growth, yield and economics of rabi sweet corn (Zea mays L., var. saccharata Sturt) as influenced by different spacing and fertilizer levels under south Gujarat conditions

A field experiment was conducted during rabi 2011 at College Farm, Department of Agronomy, College of Agriculture, Navsari Agricultural University, Navsari to assess the response of rabi sweet corn (Zea mays L. var. saccharata Sturt) to spacing and fertilizer levels under south Gujarat conditions. The experiment comprising 16 treatment combinations consisting of four levels of plant spacing (60×15, 45×20, 30×30 and 60×30 cm) and four fertility levels (60–30, 90–45, 120-60 and 150-75 kg N-P2O5/ha). Plant spacing of 60×30 cm, 45×20 cm and 60×15 cm attained significantly higher plant height compared to 30×30 cm. While stem diameter and number of leaves per plant were not influenced by different spacing levels. The sweet corn plants exhibited significantly maximum values of yield attributes viz., cob length, cob girth, under spacing of 45×20 cm. Number of cobs per plant and cob yield per plant were higher under spacing of 60×30 cm. Highest green cob yield was recorded at spacing of 45×20 cm closely followed by 30×30 cm. The highest net returns (Rs. 60568/ha) and BCR (5.52) were recorded under plant spacing of 45×20 cm. The growth of sweet corn in terms of plant height, number of leaves per plant and stem diameter were maximum with application of 150-75 kg N-P2O5/ha. The sweet corn plants exhibited maximum values of yield attributes viz., number of cobs per plant under 150-75 kg N-P2O5/ha and found at par with those recorded under 120-60 kg N-P2O5/ha. Whereas cob length and cob girth were under 120-60 kg N-P2O5/ha and found at par with those recorded under 150-75 kg N-P2O5/ha. Application of 150-75 and 120-60 kg N-P2O5/ha significantly increased green cob yield over 90–45 and 60–30 kg N-P2O5/ha. Economic evaluation of fertility levels revealed that the highest net returns of Rs. 59509/ha and BCR of 5.46 were recorded with application of 120-60 kg N-P2O5/ha. Thus, from the present study, it seems quite logical to conclude that higher production and net returns from rabi sweet corn (var. Madhuri) can be secured by sowing the crop at 45×20 cm spacing and fertilizing with 120-60 kg N-P2O5/ha on clayey soil under south Gujarat conditions.

Genetics of drought tolerance at seedling and maturity stages in Zea mays L.

Shortage of irrigation water at critical growth stages of maize is limiting its production worldwide. Breeding drought-tolerant cultivars is one possible solution while identification of potential genotypes is crucial for genetic improvement. To assess genetic variation for seedling-stage drought tolerance, we tested 40 inbred lines in a completely randomized design under glasshouse conditions. From these, two contrasting inbred lines were used to develop six basic generations (P1, P2, F1, F2, BC1F1, BC2F2). These populations were then evaluated in a triplicated factorial randomized complete block design under non-stressed and drought-stressed conditions. For statistical analyses, a nested block design was employed to ignore the replication effects. Significant differences (p≤0.01) were recorded among the genotypes for investigated seedling-traits. Absolute values of fresh root length, fresh root weight, and dry root weight lead to select two genotypes, one tolerant (WFTMS) and one susceptible (Q66). Estimates of heritability, genetic advance, and genotypic correlation coefficients were higher and significant for most of the seedling-traits. Generation variance analysis revealed additive gene action. Narrow-sense heritability [F2 ≥ 65; F∞ ≥ 79] revealed the same results. Generation mean analysis signified additive genetic effects in the inheritance of cob girth, non-additive for plant height, grains per ear row and grain yield per plant, and environmental for ear leaf area, cob length, grain rows per ear, biomass per plant, and 100-grain weight under drought-stressed conditions. For conferring drought-tolerance in maize, breeders can adopt the recombinant breeding strategy to pyramid the desirable genes.

Effect of site specific nutrient management on production and productivity of maize (Zea mays L.) under mid hill condition of Chhatisgarh

A field experiment was conducted in two consecutive Kharif seasons of 2012 and 2013 at Ambikapur to work out the effect of nutrient management on growth and development behavior of maize ( Zea mays L.) hybrids. Plant height, leafarea, dry matter accumulation, and crop growth rate (CGR) were significantly higher with site-specific nutrient management (SSNM) over the recommended dose of fertilizer (RDF) under conservation agriculture. On the maize hybrids, 'PMH 3' recorded significantly highest plant height, dry-matter accumulation and crop growth rate at various stages which was at par with 'PMH 1' but significantly superior to other hybrids. Significantly lowest leaf- area, dry matter accumulation and crop growth rate was recorded with 'HQPM 1'. SSNM recorded highest yield attributes, viz ., cob length (cm), cob girth (cm), grain rows/cob, grains/row, shelling per cent and 1000 grain weight (g) significantly higher over 50 per cent RDF but at par with 100 per cent RDF. SSNM recorded significantly highest cob yield and grain yield (kg/ha) over 100 and 50 per cent RDF. With regards to maize hybrids 'PMH 3' recorded yield attributes, viz ., cob length (cm), cob girth (cm), grain rows/cob, grains/row, shelling per cent and 1000 grain weight (g) which was at par with 'PMH 1' but significantly superior to other hybrids. Significantly lowest yield was recorded by 'HQPM 1'.

Response of yield and quality parameters of maize hybrid to single super phosphate and gypsum

Maize has the highest potential yield and responds greatly to applied fertilizers especially in the irrigated conditions in Tamil Nadu. Phosphorus and sulphur are the major yield limiting factor after nitrogen in the study area- Sivagangai district of Tamil Nadu. Therefore, this study was initiated with the aim of increasing the yield of hybrid maize by optimizing the phosphorus and sulphur fertilizers in the farmer's field. The experiment was laid out in a Factorial Randomized Block Design replicated thrice with five levels of phosphorus viz., 0, 50, 75, 100, 125 kg P 2 O 5 per ha and five levels of sulphur viz., 0, 20, 40, 60, 80 kg S per ha. The results revealed that plant height, dry matter production, cob length, cob girth, the number of grains per cob and hundred grain weight were significantly increased with increased dose of P and S, and significantly higher at 125 kg P 2 O 5 per ha and 80 kg S per ha. Similarly, the maize grain yield was higher at 125 kg P 2 O 5 per ha (5964 kg per ha) and 80 kg S per ha (5035 kg per ha). Interaction of phosphorus and sulphur was additive with respect to growth and yield of maize.

Genetic Diversity and Structure of Maize Accessions of North Western Himalayas Based on Morphological and Molecular Markers

Genetic diversity among 48 maize genotypes was determined using 11 morphological traits, 4 biochemical traits and 29 SSR primers. To assess the genetic diversity, data on morphological traits were recorded during the year 2013–2014 using standard maize descriptors. Eleven morphological traits observed across the 48 maize genotypes showed wide variation and grouped various test genotypes into two clusters. Based on the mean performance of genotypes, LM-19-07 and HKI-1348 were found superior for grain yield/plant, cob length, cob girth, kernel row/ear among all the genotypes. Protein content of LM-02-08 was the highest among all the genotypes. CML193 was found superior for iron and zinc content. Carotenoid content of LM-19-07 was higher as compared to checks. At molecular level, 29 SSR primers amplified 96 polymorphic alleles with an average of 2.16 alleles per primer. Size of amplified alleles ranged from 50 to 500 bp. Mean polymorphic information content was 0.43 showing high level of SSR polymorphism. Cluster analysis based on SSR data differentiated 48 maize genotypes into two major clusters. Bayesian model-based structure analysis assigned genotypes into two clusters and also showed the extent of admixture within individuals. Clustering pattern of maize genotypes based on SSR marker profiles was different from that of morphometric traits. Based on the pooled analysis at morphological, biochemical and molecular level, genotype LM-19-07 was found superior as well as most distant among all the accessions under study. So the genotype LM-19-07 could be used in future breeding programmes for genetic improvement in maize.