Cob Yield Research Articles

Effect of zinc application on growth and yield of baby corn (Zea mays L.) in lateritic soil of West Bengal

A field experiment was conducted during rabi season of 2017-18 at agricultural farm, Palli Siksha Bhavana, Visva-Bharati, Sriniketan, West Bengal, to study the “Effect of zinc application on growth, yield and economics of baby corn (Zea mays L.) in lateritic soil of West Bengal”. The experiment was laid out in Factorial RBD having two factors: one with two levels of soil application of ZnSO4; 0 and 25 kg ha-1 and other with four levels of foliar spray of ZnSO4; no foliar spray, 25 DAS, 40 DAS and twice at 25 DAS & 40 DAS. There were eight treatment combinations with each treatment replicated thrice. Soil application of ZnSO4 @ 25 kg ha-1 exhibited significantly higher growth attributes (viz. plant height, number of leaves/plant, LAI, dry matter accumulation, crop growth rate) and yield attributes (viz. number of cobs per plant, corn and cob weight, corn and cob length, corn and cob girth and also corn yield, cob yield, husk yield and green fodder yield) of baby corn, than no soil application of ZnSO4. Foliar spray of ZnSO4 applied twice at 25 DAS & 40 DAS gave the highest yield components and yield in baby corn. However, this was statistically at par with foliar spray of ZnSO4 at 40 DAS and 25 DAS. Combined soil application of ZnSO4 @ 25 kg ha-1 and foliar spray twice at 25 DAS & 40 DAS interacted significantly and produced higher number of cobs per plant, number of cobs per hectare of baby corn cultivation. This was at par with soil application of ZnSO4 at 25 kg ha-1 and foliar spray at 40 DAS and significantly higher than foliar spray at 25 DAS.

Yield and economics of sweet corn (Zea mays L. Saccharata) as influenced by plant densities and nitrogen management in irrigated condition

A field experiment was conducted during kharif 2017-18 to study the yield and economics of sweet corn (Zea mays L. Saccharata) as influenced by plant densities and nitrogen management in irrigated condition at Agricultural Research Station, Siruguppa, Karnataka. The soil of the experimental site was clay in texture, low in organic carbon, available N, medium in available phosphorus and high in potassium. The experiment consisted of sixteen treatment combinations of four plant densities viz., S1:1,11,111, S2:74,074, S3:83,333 and S3:55,555 plants ha-1 in main plots and four nitrogen levels F1:150 kg N ha-1, F2:187.5 kg N ha-1, F3:225 kg N ha-1 and F4: 262.5 kg N ha-1 in sub plots. Plant density 1,11,111 plants ha-1 recorded significantly higher fresh cob yield (13350 kg ha-1) and fresh stover yield (25299 kg ha-1) compared to other plant densities. On the contrary yield parameters viz., number of grains per row, number of rows per cob, cob girth, cob length, cob weight and test weight were higher in plant density of 55,555 plants ha-1 compared to other plant densities. Among the nitrogen levels, application of 262.5 kg N ha-1 registered significantly higher fresh cob yield (13866 kg ha-1), fresh stover yield (24873 kg ha-1) and yield parameters viz., number of grains per row, number of rows per cob, cob girth, cob length, cob weight and test weight as compared to other nitrogen levels. Higher net returns (Rs. 1,40,876 ha-1) and minimum B:C (2.95) was recorded with plant density of 1,11,111 plants ha-1 compared to rest of the plant densities and it was on par with 83,333 plants ha-1 with net returns (Rs.137521 ha-1) and B:C (3.36). Among the nitrogen levels, application of 262.5 kg N ha-1 has recorded significantly higher net returns (Rs. 1,59,020 ha-1) and B:C (3.61) compared to other N levels and it was closely followed application of 225 kg N ha-1.

Yield and nutrient uptake of baby corn (Zea mays L.) Genotypes as influenced by crop geometry and fertility levels

A field experiment was conducted to study the effect of crop geometry and fertility levels on the yield and nutrient uptake of baby corn (Zea mays L.) genotypes. The experiment was laid out in split plot design with main plot factor comprising of 4 treatment combinations of crop geometry(S) and fertility levels(F) viz. S1F1(65cm × 16 cm, RDF), S1F2(65cm × 16 cm, 150%RDF), S2F1(65cm × 12 cm, RDF) and S2F2,(65cm × 12 cm, 150%RDF) and sub plot factor comprising of 2 baby corn genotypes (G) viz. G1(BC-18K-ZIII-1) and G2(BC-18K-ZIII-2). The combination of (S1F2)G2 recorded the maximum first baby cob yield and baby corn yield. The combination of (S1F2)G1 recorded maximum harvest index. The total N and K uptake was significantly higher for S2, F2 and G2 as compared to S1, F1 and G1, respectively. The P and K uptake for cob husk was maximum with the combination of (S2F2)G2.

Rate Determination of Nitrogen and Phosphorus Fertilizers for Green Maize Under Irrigation

A study was conducted on a research station at Kobo sub-center of Sirinka Agricultural research Center for two years to determine the optimum rates of N and P fertilizers for green maize production under irrigation in Kobo-Girana irrigation valley. Four levels of N (0, 46, 92 and 138 kg N ha -1 ) with three levels of P fertilizer (0, 23 and 46 kg P 2 O 5 ha -1 ) were factorially combined and laid in RCBD design with three replications. A uniform irrigation water depth and interval was applied to all plots based on maize’s irrigation water requirement determined for the area. The crop was irrigated a total amount of 500 mm irrigation water at 7 days interval starting from the development stage. Phosphorus fertilizer was applied all at planting. While, N fertilizer was applied in split, 1/3 at planting, 1/3 at knee height and 1/3 at tasseling stage. The result shows that there was no significant (p>0.05) interaction of N and P fertilizers on the cob yield, cob number, cob length and cob diameter of green maize. However, the main effect of N fertilizer had significant (p < 0.05) effect on the cob yield, cob number, cob length and cob diameter of green maize. The main effect of application of P fertilizer had insignificant (p>0.05) effect on the cob yield of green maize, which is attributable to the medium to high levels of Olsen’s extractable available P in bottom valleys of alluvial soils of Kobo where the study site laid. The highest cob number (51556) and cob weight (12.0 t ha -1 ) was recorded from application of 138 kg N ha -1 followed with statistically insignificant (p>0.05) difference by the cob number (49020) and cob weight (11.1 t ha -1 ) obtained from application of 92 kg N ha -1 . The partial budget and the sensitivity analysis result considering 15% possible price fluctuation show that the highest marginal rate return of 421.7% was obtained from application of 92 kg N ha -1 . While, the lowest marginal rate return of 378.8% was recorded from application 138 kg N ha -1 . Therefore, application of 92 kg N ha -1 is recommended for maximum and economic return of green maize production under irrigation in Kobo valley. Keywords: Green maize, kobo, irrigation, nitrogen, phosphorus. DOI: 10.7176/JNSR/10-3-03 Publication date: February 29 th 2020

Nitrogen use efficiency of extra early maize varieties as affected by split nitrogen application in two agroecologies of Nigeria

Poor yield of maize has been attributed to low soil N since maize requires high Nitrogen for optimum productivity. Field experiments were conducted in the late season of 2014 at IITA, Research Farms, in Ibadan and Mokwa. The research was to evaluate the effects of split N fertilizer on nitrogen use efficiency of extra early maize varieties. Arrangement was 5 x 8 factorial fitted into Randomized Complete Block Design, with four replications. Extra early maturing maize varieties (2013 TZEE-W DT STR, TZEE-Y Pop STR C4, TZEE-W Pop STR C5, 2013 TZEE-Y DT STR, and 99 TZEE-Y STR QPM) with Nitrogen fertility rates ( 0 kg N ha-1 (Control), 30 kg N ha-1 single, 60 kg N ha-1 single, 60 kg N ha-1 split (30:30) applied at 2 and 4 weeks after sowing (WAS), 90 kg N ha-1 split 60:30 applied at 2 and 4 WAS, 90 kg N ha-1 split (30:30:30) applied at 2, 4 and 6 WAS, 120 kg N ha-1 split (60:60) applied at 2 and 4 WAS and 120 kg N ha-1 split (30:60:30) applied 2, 4 and 6 WAS). Data collected were subjected to Analysis of Variance procedure and significant means were separated using Duncan’s Multiple Range Test at p<0.05. Results showed that maize variety 2013 TZEE-W DT STR produce highest number of leaves, plant height, leaf area, cob yield (3.33, 3.15 t ha-1), grain yield (2.57, 2.38 t ha-1) and Nitrogen use efficiency (33.03, 28.95%) at Mokwa and Ibadan respectively. Split application of 90 kg N ha-1 as (60:30) at 2 and 4 WAS produce significantly (p<0.05) higher 1000 grain weight, cob yield (3.90, 3.73 t ha-1) and grain yield (2.99, 2.80 t ha-1) at Mokwa and Ibadan respectively. The control produced significantly reduced dried cob and grain yield by (85, 81%) and (84.4, 80.4%) in Mokwa and Ibadan respectively, compared to the best rate of 60:30 split N application. The N application of 30 kg N ha-1 as single dose had the highest Nitrogen use efficiency (51.3, 43.0 %) in both Mokwa and Ibadan, which was significantly different (p<0.05) from the rest treatments. Across the varieties used in both locations, Mokwa agro-ecology zone proved to be a favourable location for higher yield of extra early maize varieties. The study concluded that application of 30kgN/hectare at two weeks after sowing efficiently improved Extra early maize varieties and is thus recommended as low input package for resource poor farmers.

Assesment and effect of normal and saline irrigation on growth parameters of maize cultivar jasaura village of district Kannauj, U.P.

The field experiment was conducted during the year 2016 and 2017 at village Jasaura district Kannauj, Uttar Pradesh. Plant height at 75 DAS was ranged from 135 – 157.33 and 134 – 158.41 cm. Plant height at harvest was ranged from 175 – 204.62 and 173. – 206.67 cm. Plant girth was ranged from 6.01 – 7.03 and 5.97 – 7.13 cm. No. of leaves were found 15.46 – 16.42 and 15.41 – 16.17. The no. of cobs/ plant were found 1.00 – 1.04 and 1.00 – 1.04. The no. of grain rows/cobs were ranged from 13.70 – 15.50 and 13.66 – 15.50. The no. of grains/row was ranged from 23.94 – 26.71 and 22.93 – 26.65. The no. of grains/cob was ranged from 336.12 – 418.21 and 313.36 – 403.16. The cob length was ranged from 15.26 – 20.11 and 14.87 – 20.81. The cob circumference was found 13.87 – 15.88 and 13.49 – 15.90. The cob yield was found that 61.35 – 87.45 and 57.52 – 91.82. The grain yield was ranged from 43.85-70.32 q ha-1 and 40.50-73.92 q ha-1. The stover yield was ranged from 116.65-142.87 q ha-1 and 114.25-143.15 q ha-1. All the parameters were obtained from 2016 to 2017 year respectively

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.

Physiological assessment of iron and zinc biofortification on growth and yield parameters of sweet corn

Field experiment was carried out during kharif 2017 and 2018 in black soil at farmer field at Kumarnahally village, Huvina hadagali Tq, Bellary District representing the Northern Dry Zone (Zone-II) which is located at latitude of 15.04’ N, longitude of 75.94' E and 561 meters which is above mean sea level to study the physiological assessment of iron and zinc biofortification on growth and yield parameters of sweet corn (Zea mays L. Saccharata) to evaluate and analysis of sweet corn through biofortification to achieve higher growth and yield parameters. Pooled data both years indicated that seed treatment with ZnSO4 @ 0.5 % + FeSO4 @ 0.5 % and foliar spray of ZnSO4 @ 1.0 % + FeSO4 @1.0 % recorded significantly higher total dry matter (196.3, 203.8 and 200.1 g plant-1 at 30, 60 DAS and at harvest, respectively) and also higher photosynthetic rate (17.2, 33.5 and 32.7 µ mol CO2 m-2 s-1 at 30, 60 DAS and at harvest respectively. Similarly Fresh cob yield was noticed with seed treatment by ZnSO4 @ 0.5 % & FeSO4 @ 0.5 % and foliar spray of ZnSO4 @ 1.0 % & FeSO4 @1.0 % which was on par with seed treatment with ZnSO4 @ 0.5 % + foliar spray of ZnSO4 @ 1.0 % + FeSO4 @1.0 % during the year 2017, 2018 and pooled data.

Effect of morpho-physiological assessment of iron and zinc biofortification on yield and quality of sweet corn (<em>Zea mays L. Saccharata</em>)

Field experiment was carried out during kharif 2017 and 2018 in black soil at farmer field at Kumarnahally village, Huvina hadagali Tq, the experiment was laid out in a randomized block design (RCBD) comprising 13 treatments replicated thrice. Bellary District representing the Northern Dry Zone (Zone-II) which is located at latitude of 15.04’ N, longitude of 75.94' E and 561 meters which is above mean sea level to study the effect of morpho-physiological assessment of iron and zinc biofortification on yield and quality of sweet corn (Zea mays L. Saccharata) to evaluate and analysis of sweet corn through biofortification to achieve higher yield and quality parameters. The results of pooled data revealed that seed treatment by ZnSO4 @ 0.5% & FeSO4 @ 0.5% and foliar spray of ZnSO4 @ 1.0% & FeSO4 @1.0% which was on par with seed treatment with ZnSO4 @ 0.5% + foliar spray of ZnSO4 @ 1.0% + FeSO4 @1.0% recorded significantly higher number of seeds per row, number of seed rows per cob, cob length, cob girth, cob weight and fresh cob yield and also quality parameter like protein content, reducing sugar, non reducing sugar, zinc concentration in grain and iron concentration in grain.

Maize yields and carbon pools in response to poultry litter, rock phosphate and P-solubilizing microorganisms

ABSTRACT: The acid release of phosphates from rock phosphates (RP) and the retention of ammonium by inorganic phosphates have been studied separately in composting; however, there is a gap in the knowledge of combined application of RP with organic residues and microorganisms. The objectives were to evaluate the combined application of fresh poultry litter (PL) with RP and P-solubilizing microorganisms (M) on soil organic matter pools, microbial biomass C (MB-C) and on whole-plant silage maize and grain yields. Two field experiments tested the effects of timing of applications of PL (8 Mg ha–1), RP (4 Mg ha–1) and microorganisms on soil organic matter pools, nutritional aspects and productive components of maize crop whole-plant silage. A second experiment evaluated the effects of RP doses (0, 3, 6 and 9 Mg ha–1) with a fixed dose of PL (8 Mg ha–1) on maize grains. Application of PL+RP decreased soil organic C, while RP alone increased the humin fraction C compared to the control. The MB-C in soil with PL and PL+RP+M increased in comparison to the control and the RP. The application of PL, based on an average of fall and spring, increased leaves + stem dry matter, while in the fall on its own, the highest cob yield was observed in the combination of PL+RP, showing synergistic effects. The best ratio of poultry litter to rock phosphate combination is 2:1 in the anticipated fall application on the maize silage crop or immediate application on the maize grain crops.

Triple-row system with a wider drip-line lateral spacing for two drip-irrigated sweet corn cultivars

Abstract: The objective of this work was to evaluate the use of both single- and triple-row production systems in two drip-irrigated sweet corn cultivars under dry Mediterranean climate conditions. A two-year field experiment (2017 and 2018) was carried out in clay loam soil. The following three combinations spacing between crop rows and drip-line lateral spacing, with three replicates for each cultivar, were applied: single rows at 75 cm spacing, with one drip-line lateral spacing for each crop row; single rows at 75 cm row spacing, with one drip-line lateral spacing for three crop rows; and triple rows, 37.5 cm apart, on 225 cm centers, with one drip-line lateral spacing for each triple row. The responses of both cultivars were similar. In addition, husked cob yield and irrigation water use efficiency (IWUE) significantly reduced as the drip-line lateral spacing increased in single rows. Yield loss was 35.2% in relation to the 75 cm spacing. However, when the triple-row system with 225 cm drip-line lateral spacing was adopted, yield and IWUE were noticeably improved, and the yield loss was moderated to 16%, due to the improvement in soil water conditions in the triple rows. For improved yield and IWUE, the combination of triple rows with the 225-cm drip-line lateral spacing is an efficient drip-irrigated planting pattern for sweet corn production in dry Mediterranean climate conditions.

On-farm performance and farmers’ participatory assessment of new stress-tolerant maize hybrids in Eastern Africa

The development and deployment of high-yielding stress tolerant maize hybrids are important components of the efforts to increase maize productivity in eastern Africa. This study was conducted to: i) evaluate selected, stress-tolerant maize hybrids under farmers’ conditions; ii) identify farmers’ selection criteria in selecting maize hybrids; and iii) have farmers evaluate the new varieties according to those criteria. Two sets of trials, one with 12 early-to-intermediate maturing and the other with 13 intermediate-to-late maturing hybrids, improved for tolerance to multiple stresses common in farmers’ fields in eastern Africa (drought, northern corn leaf blight, gray leaf spot, common rust, maize streak virus), were evaluated on-farm under smallholder farmers’ conditions in a total of 42 and 40 environments (site-year-management combinations), respectively, across Kenya, Uganda, Tanzania and Rwanda in 2016 and 2017. Farmer-participatory variety evaluation was conducted at 27 sites in Kenya and Rwanda, with a total of 2025 participating farmers. Differential performance of the hybrids was observed under low-yielding (<3 t ha−1) and high-yielding (>3 t ha−1) environments. The new stress-tolerant maize hybrids had a much better grain-yield performance than the best commercial checks under smallholder farmer growing environments but had a comparable grain-yield performance under optimal conditions. These hybrids also showed better grain-yield stability across the testing environments, providing an evidence for the success of the maize-breeding approach. In addition, the new stress- tolerant varieties outperformed the internal genetic checks, indicating genetic gain under farmers’ conditions. Farmers gave high importance to grain yield in both farmer-stated preferences (through scores) and farmer-revealed preferences of criteria (revealed by regressing the overall scores on the scores for the individual criteria). The top-yielding hybrids in both maturity groups also received the farmers’ highest overall scores. Farmers ranked yield, early maturity, cob size and number of cobs as the most important traits for variety preference. The criteria for the different hybrids did not differ between men and women farmers. Farmers gave priority to many different traits in addition to grain yield, but this may not be applicable across all maize-growing regions. Farmer-stated importance of the different criteria, however, were quite different from farmer- revealed importance. Further, there were significant differences between men and women in the revealed-importance of the criteria. We conclude that incorporating farmers’ selection criteria in the stage-gate advancement process of new hybrids by the breeders is useful under the changing maize-growing environments in sub-Saharan Africa, and recommended to increase the turnover of new maize hybrids.

Evaluation of Fresh Ear Yield And Quality Performance In Super Sweet Corn

Aim of this study is determine to fresh ear yield and quality characters of sweet corn varieties which Vega, Challenger, Sentinel, HYRIX 39, and HYRIX 53 in two location in Turkey. The research was conducted on randomised blocks design with four replication in Bafra and Tekkekoy location. The experiment was caried out evaluate the yield and quality performance of some sweet corn genotypes as well as demonstrate unfamiliar supersweet corn concept in Turkey. In the research were obserwed some yield component and quality characters such as flowering time, plant length, first cob length, grain yield, cob diameter, cob length, number of rows in the cob, amount of grains in row, number of marketable cobs per plant, wet cob harvest time, wet cob yield, grain cob ratio, grain moisture, dry grain yield. It was found that sweet corn genotype are significantly different in terms of yield and quality characteristics. The highest wet cob yield was 24.238 t ha-1 in Hybrix 39 super sweet. Super sweet corn has an important potential in sweet corn cultivation due to high yield of dry grains and its high maintenance rate of sugar raito in the long term after harvesting. Statistical analysis showed that the effect of genotype and the environment, as well as their interactions, had a significant impact on the yield of sweet corn hybrids. The presented results have demonstrated the poerformance of some sweet corn in Turkey. This work is intended to inspire similar studies using other sweet corn varieties and also to encourage the wide-scale production sweet corn in Turkey.

Moments and number of defoliated leaves and hybrid corn productivity

AbstractObjectives: To determine the effect of the time and the number of lower leaves defoliated, on the productivity of hybrid corn (Zea mays L.). Methodology: Randomized complete blocks design was used, with arrangement of split plot and four replications, using the hybrid cultivar DK 7088. The plots corresponded to the defoliation times: 0, 14 and 28 days after pollination (DAP) and the subplots, number of defoliated leaves (DL): zero, two,four and six. The leaves were defoliated just below the ear, from top to the bottom. The total number of treatments was 12. Scott-Knott statistical test with a level of 5 % was used for the comparison of means. The traits studied were grain weight per ear, ear weight and grain yield per hectare. Results: The interaction between defoliation time and number of lower defoliated leaves was significant (P &lt; 0.05) for grain weight per ear, ear weight andgrain yield. The defoliation of two, four and six leaves during pollination reduced the grain weight per ear, weight per cob and grain yield, being significantly lower than the no defoliated plants. At 14 and 28 days after pollination, defoliation did not affect significantly (P &gt; 0.05) grain yield, but grain weight per ear and ear weight decreased (P&lt; 0.05). Conclusions: The defoliation of lower leaves made during the pollination, reduces the grain weight per ear, ear weight and grain yield, while defoliation 14 days after pollination did not affect significantly the grain yield per hectare.Keywords: Zea mays, defoliation, leaves, grain yield

Yield Performance of Organic Baby Corn (Zea Mays L.) as Influenced by Nutrient Management and Moisture Conservation Practices in Sandy loam Soils of Assam

A field experiment was conducted during the rabi season of 2016-17 to study the effect of nutrient management and moisture conservation practices on yield attributing characters, yield and economic return of organic baby corn grown in a sandy loam soil under rainfed condition. The experiment was laid out in RBD factorial design with three replications. PAC 321 was used as the test variety of baby corn. Among the treatments enriched compost @ 2.5 t ha-1 has shown the significantly better results with respect to yield attributing characters and cob yield followed by application of FYM @ 2.5 t ha-1+lime+ash (1000:10:1). Treatments with straw mulch @ 2 t/ha recorded significantly higher results with respect to different yield attributing characters, cob yield, green fodder yield and high monitary return with B:C ratio.

English

The conversion of tropical field corn genotypes into sweet corn could broaden the genetic base and improve yield and adaptation of sweet corn varieties. In this study, the performance of shrunken-2 (sh2) super-sweet corn populations derived from crosses between a sh2 population and tropical field corn genotypes were evaluated in Ibadan. Experiments were conducted using randomised complete block design with three replicates. Data were collected on agronomic and fresh ear yield traits, and then subjected to analysis of variance. Significant genotypic differences were observed among the populations with most of the derived populations significantly superior to the donor population for most of the traits. Yield of marketable cobs ranged from 5.80 to 7.63 t/ha (mean = 6.84 t/ha). Six derived populations had significantly higher yield of marketable cobs than the donor population. On the average, 83.1% of the number of cobs harvested was marketable. Husk cover scores ranged from 2.8 to 6.8, with all the derived populations having significantly lower husk cover scores than the donor population. The results indicated that the conversion of the field corn genotypes into super-sweet corn was effective in the development of new super-sweet corn populations. The observed genetic differences could be exploited in further breeding programmes. Key words: Fresh ear yield, husk cover, shrunken-2 super-sweet corn, yield of marketable cobs &nbsp

Effect of soil amendment with Gliricidia sepium and Tephrosia vogelii biomass on maize yield at Makoka in Malawi

Several studies assessing the effect of leguminous tree biomass such as Gliricidia sepium and Tephrosia vogelii on maize yield have been undertaken. There has been limited knowledge on the efficacy of leguminous tree biomass on maize yield when grown after a crop with a high nitrogen (N) demand. One such crop is cotton. The current study was undertaken with the objective of determining the efficacy of either gliricidia or tephrosia biomass application with or without inorganic fertilizer on maize yield cultivated after cotton and also after land fallowing. Significant variations in grain yield (P = 0.0038) were obtained in the second cropping season (2016/17) but not in the first cropping season (2014/15), except maize stover (P < 0.0016). Significant variations were also obtained during 2016/17 season with respect to maize cob yield (P < 0.0041) and stover yield (P = 0.0062). Grain yield was significantly higher where inorganic fertilizer was applied with gliricidia biomass than where inorganic fertilizer was applied alone. A similar trend was also observed during the first cropping season though not significantly different. Lower grain yield was obtained when cotton crop preceded maize crop indicating a need for a higher N fertilizer dose for maize crop cultivated after cotton. Application of a half dose of inorganic fertilizer together with gliricidia biomass showed high and steady grain yield over the yield obtained when inorganic fertilizer was applied alone. It is concluded that soil fertility amendment with inorganic fertilizer is needed after a cotton crop. Also, the use of a half dose of inorganic N fertilizer with gliricidia was effective, suggesting that a full dose with gliricidia biomass was rather surplus to the requirements for maize production. Our study shows that farmers can save nearly half of the inorganic N fertilizer required by maize under gliricidia-maize system.

Effects of Inter- and Intra-Row Spacing on Growth, Green Cob Number and Biomass Yield of Maize (Zea mays L.) Varieties at Agarfa, Southeastern Ethiopia

Maize ( Zea mays L.) is an important grain crop of the world and it ranks second, after wheat in hectarage and first in total production and productivity. In Ethiopia, maize has increasingly become a popular crop with steady growth in production area and yield. However, green cob maize production packages, including its appropriate spacing, are not yet determined. Evidences on effects of inter and intra-row spacing on growth and green cob yield of maize are not well explored. Therefore, this study was conducted at Agarfa from March 2015 to July 2015 to determine the effects of inter-and intra-row spacing on growth, green cob number and biomass yield of maize (Zea mays L) varieties under supplemental irrigation. The experiment was laid out in a randomized complete block design with factorial combination of four inter-row (55 cm, 65 cm, 75 cm, and 85 cm) spacing, two intra-row spacing (25 cm and 30 cm) and two maize varieties (Melkassa-II and BHQPY-545) with three replication. Data were collected on growth, green cob number and biomass yield and analyzed using GenStat, (2012) The experiment result revealed that leaf area and number of cobs per plant were highly significantly (P<0.01) affected by inter-row spacing x variety while cob length, number of cobs per hectare and above ground fresh biomass yield were significantly (P<0.05) affected by inter-row spacing x variety. The highest cob number (65232.32 ha -1 ) was recorded for variety BHQPY-545 and (61739.39 ha -1 ) for variety Melkassa-II at narrowest inter-row spacing of 55 cm (Table 5). Similarly, the highest fresh biomass yield of 51.3 and 48 ton ha -1 was obtained from variety BHQPY-545 and Melkassa-II respectively at 55 cm inter-row spacing. In general, significantly higher number of marketable green cobs and aboveground fresh biomass yield were obtained at closer inter-and intra-row spacing for maize varieties tested in the study area. Therefore, it can be concluded that spacing combination of 55 cm x 25 cm favored attaining of higher economic returns, green cob number and fresh biomass yield of maize in the area under supplemental irrigation. Keywords : Phenology, Plant Density, Population, Economic Benefit, Biomass DOI : 10.7176/JBAH/9-9-05 Publication date :May 31 st 2019

English

Inbred line development requires information on the nature and magnitude of genetic variability and transmissibility of desired trait in source populations. In this study, the level of genetic variability, heritability and genetic advance of thirteen agronomic and fresh yield traits among twelve shrunken-2 super-sweet corn populations were evaluated. Field experiments were conducted for two years in Ibadan, Nigeria using a randomised complete block design with three replicates. Estimates of genetic variability components, broad-sense heritability and genetic advance were computed for each trait. All the traits exhibited significant genotypic differences. Genotypic variance was significant for number of marketable cobs, yield of cobs, number of cobs, number of kernel rows, husk cover, ear height and days to anthesis, while environmental variance was significant for all the traits. Phenotypic coefficients of variation were higher than the corresponding genotypic coefficients of variation for all traits. Broad-sense heritability ranged from 22.2% for anthesis-silking interval to 85.1% for husk cover. The genetic advance was high (32.7%) for husk cover, medium (12.0%) for yield of cobs and low for other traits. Genetic variability was present among the shrunken-2 super-sweet corn populations. Opportunities abound for further improvement of the populations and extraction of lines for hybrid seed production. Key words: Broad-sense heritability, genotypic coefficient of variation, husk cover score, sweet corn, yield of marketable cobs. &nbsp

Performance of Baby Corn (Zea Mays L.) in Integration of Organic and Inorganic Nitrogen

Nitrogen (N) fertilization mostly determines the productivity of a crop. The supply of N can be ensured in both inorganic and organic means. Slowly released organic N can be combined with inorganic N to minimize the detrimental effect of chemical fertilizers to environment as well as to ensure the sustainable production. To observe the response of baby corn in integration of organic and inorganic N field experiments were conducted in N deficit soil in consecutive winter and summer. There were five nutrient levels as treatment in the experiment. The treatments used in the winter season were T1=N 0 kg + CD 15 t ha-1, T2=N 60 kg + CD 15 t ha-1, T3= N 90 kg + CD 10 t ha-1, T4= N 120 kg + CD 5 t ha-1 and T5= N 150 kg + CD 0 t ha-1 while in the summer season T1=N 30 kg + CD 15 t ha-1 varied and others remained same as in the winter season. The lowest cob yield without husk was found where minimum inorganic N was combined with organic N in both seasons. Plant received only N from inorganic source represented highest cob yield. Statistically similar yield was also obtained from one combination of inorganic and organic N (120 kg N + 5 ton CD ha-1), where the rate of inorganic N was 20% lower than that of sole inorganic N source. Between seasons, significantly positive yield response was recorded in winter irrespective of nutrient levels. Therefore, one fifth of inorganic N application can be minimized in terms of integrated N management from organic and inorganic sources without affecting potential yield of baby corn.