Greater Number Of Tillers Research Articles

Alternative Agronomic Management Practices Through Fertilizer, Irrigation, and Plant Density Adjustments for Hybrid Fodder Sorghum (<em>Sorghum bicolor</em> L. Moench)

Purpose: The basal fertilizer recommendation for growing hybrid fodder sorghum varieties in uplands involves relatively high quantities of Urea, TSP, and MOP, with rates of 100:90:65 kg/ha for SX-17 and 150:62:37 kg/ha for Dairy green. For both initial and ratoon crops, it is recommended to apply 150 kg/ha of urea as a top dressing. This study investigated the impact of reducing the fertilizer application rate to 75% and employing alternative agronomic practices on hybrid fodder sorghum varieties grown in lowland fallow paddy fields in the dry zone during the Yala and third seasons.Research Method: The agronomic management practices, including four basal fertilizer rates (Urea:TSP: MOP) of 100:90:65 (BD1), 150:62:37 (BD2), 75:68:49 (BD3), and 113:47:28 (BD4); two top-dressing urea fertilizer rates of 150 (TD1) and 112.5 kg/ha (TD2); two plant spacing configurations of 45x30 (WS) and 45x15 cm (NS); and two irrigation interval regimes, 5 days up to 30 days followed by 8 days (SI) and 7 days up to 30 days followed by 10 days (LI) were investigated. These factors were combined into four agronomic management packages: AMP1 (BD1, TD1, WS, SI), AMP2 (BD2, TD1, NS, SI), AMP3 (BD3, TD2, WS, LI), and AMP4 (BD4, TD2, NS, LI). The study used a split-plot design with three replicates and assessed various parameters, including plant height, stem diameter, plant weight, leaf area index (LAI), number of tillers, and fodder yield in both the initial fodder sorghum crop and the first ratoon crop. The crops were harvested when 50% of the panicles on the plants were at the milk and dough grain stages.Findings: The initial crop exhibited significantly heavier plants having wider stems when grown with higher fertilizer rates, wider plant spacing, and shorter irrigation intervals in AMP1. Irrespective of fertilizer rate and irrigation interval, the initial crops tended to have higher LAI with narrow plant spacing in AMP2 and AMP4. In the ratoon crops, wider plant spacing in AMP1 and AMP3 resulted in clumps with a greater number of tillers and heavier plants. However, the ratoon crops also exhibited higher LAI with narrow plant spacing in AMP2 and AMP4. Total fodder dry matter yield (DMY) in AMP2 and AMP4 with narrow plant spacing was significantly greater for both varieties. Furthermore, the DMY was not affected by fertilizer rate and irrigation interval.Value: Hybrid fodder sorghum varieties (SX-17 and Dairygreen) cultivated at higher plant density, along with reduced fertilizer (75%) and irrigation, can produce comparable fodder yield (21.1 and 26.1 MT/ha, respectively) to those grown at lower plant density with more fertilizer and irrigation (24.6 and 28.1 MT/ha, respectively) in lowland paddy fields during Yala and third seasons in the dry zone.

First Report of Wheat Dwarf Bunt Caused by Tilletia controversa in Pakistan

Wheat (Triticum aestivum L.) is critical to food security worldwide. Wheat dwarf bunt is caused by Tilletia controversa Kühn and can cause 70-80% losses under severe condition (Trione et al. 1989; Xu et al., 2021). In May 2022, we observed dwarf bunt disease in six fields grown with spring cultivar (Glaxy-13) in District Swat, KPK-Pakistan. Infected plants had mottling and flecking on leaves, a greater number of tillers and were smaller than healthy plants. Diseased wheat head spikes were larger, wider and thicker, had bunted kernels (sori) filled with brown-black teliospores and a strong odor like that of rotten fish. Individual fields showed 10% infected plants while no dwarf bunt was recorded in nearby fields. About 150 heads exhibiting bunted kernels were collected among the six fields. Kernels were surface sterilized with 30% NaClO for 5 min after crushing by a centrifuge machine and washed with ddH20 three times. The teliospore suspension (1×106 spores/mL) was spread on 2% soil agar plates in a growth chamber (MLR 352 H, Panasonic, USA) and incubated at 5°C with 60% relative humidity for 60 days to test for T. controversa germination or at 16°C and 60% relative humidity for 15 days (MLR 352 H, Panasonic, USA) to test for T. caries and T. laevis germination. Teliospores germinated only on plates kept at 5°C. Teliospores were morphologically identified as a T. controversa from the infected samples. They ranged in size from 15.0 to 20.5 µm diam. and the walls had deep reticulations surrounded by a transparent sheath, differing from T. laevis which has smooth teliospores and T. caries which has no sheath and reticulations on the surface (Mathre 1996). To further confirm Tilletia spp. identification, genomic DNA of our two isolates (gmd123 and gmd1234) was obtained using an extraction kit (TransGen, Beijing, China). The internal transcribed spacer (ITS) region was amplified by using ITS1/4 (White et al. 1990). A BLAST search with GenBank accession no. OR366448 and OR366450 provided additional evidence the isolates belong to the complex of species that includes the three bunt species causing diseases on wheat, with 100% matches to verified sequences for T. controversa (eg. EU257561) but also to T. laevis and T. caries. Based on disease symptoms, teliospore morphology, germination at 5°C but not at 16°C, the bunt fungus was identified as T. controversa. To fulfill Koch’s postulates, 10 mL (106 spores/mL) of germinated teliospores were injected into rhizosphere soil of Galaxy-13 cultivar at 2 leaves unfolded growth stage (Zadoks 12) and 2 mL (106 spores/mL) were injected into heads of same plants at growth stages Zadoks 61-65 with a syringe. Plants injected with sterile ddH2O were used as a control. Inoculated plants were grown in a growth chamber at 8°C with 50% humidity and 24 h light. After one month at the ripening stage, the bunted kernels of the inoculated plants were filled with black teliospores releasing a fishy smell, and the control plants did not have bunted kernels. Under an optical microscope, teliospores from the inoculated plants had reticulation surface and were measured 15 to 20.5 µm in diameter, similar to the teliospores of bunt heads from the fields. To the best of our knowledge, this is the first report of T. controversa causing dwarf bunt in district Swat, KPK-Pakistan. Because the pathogen is seedborne and soilborne, the disease may become a high risk to wheat production in Pakistan. Therefore, detection of this pathogen is very important to control the disease on time.

Adaptation of Napier grass varieties in the highlands of East Gojjam

The experiment was conducted in the East Gojjam Zone of the Amhara Regional State to evaluate the varieties of released Napier grass in the study area. The four varieties of Napier grass considered for this research experiment were Maralfalafa, ILRI- 16743, ILRI-14984 and Zehone-03 (Acc. 16819). The varieties were planted in 4 m x 3 m plots using a randomized complete block design (RCBD) with three replications at the beginning of the main rainy season. Root splits at the Debremarkos onstation and Debere Eliyas sites were planted in four rows per plot. The analysis was conducted using R software. Least significance difference (LSD) at the 5% significance level was used for the comparison of means. The combined plant height, number of tillers per plant, total fresh biomass yield per hectare (t/ha), and total dry matter yield (t/ha) did not significantly differ between the varieties. The leaf-to-stem ratios of the Napier grass varieties were significantly different. In the present study, ILRI-14984 was found to be leafier than the other tested varieties. The combined analysis of the second- and third-year data revealed significant differences in plant height, number of tillers and leaf-to-stem ratio among the tested years. The greatest plant height (152.42 cm) at harvest was found in the second year after establishment, which was 2022, whereas the number of tillers per plant was greater in the 2023 harvest season. The testing location did not affect plant height, total fresh biomass yield per hectare, or total dry matter yield per hectare. The number of tillers per plant and the leaf-to-stem ratio significantly differed among the tested locations. A greater number of tillers per plant was recorded at the Debre Eliyas testing site. Similarly, the leaf-to-stem ratio was significantly greater at the same testing site.

Impact of crop establishment techniques and weed management practices on Oryza sativa L. growth and yield

AbstractDue to increased demand, labor costs, and water scarcity, farmers look for an alternative way of rice cultivation under prevailing conventional transplanting. Direct‐seeded Oryza sativa and system of rice intensification (SRI) have been developed as superior substitutes to transplanting. However, if weeds are not controlled properly, the direct seeding method faces serious weed infestation and yield losses. In this context, a field study was undertaken during kharif growing seasons to evaluate the growth and yield of O. sativa under various crop establishment methods and weed management practices. The results revealed that system of rice intensification (SRI) method of crop establishment significantly produced taller plants, higher dry matter accumulation, a greater number of tillers per meter square, highest leaf area index, yield attributes, namely, panicle density, panicle length, and grains per panicle, and higher grain and straw yield over direct seeded rice (DSR) and transplanted O. sativa. Among the various weed management practices, penoxsulam produced significantly higher grain and straw yield. The results demonstrated that average grain yield increase with SRI was reported to be 24.11% and 23.62% over DSR and 10.47% and 12.23% over transplanted O. sativa. Among various establishment techniques, lower weed density and dry weed biomass were achieved by transplanting O. sativa. Penoxsulam herbicides significantly reduced the weed density and dry weed biomass but penoxsulam herbicide demonstrated significantly the maximum reduction in number of weeds per meter square and dry weed biomass and proved superior against complex weed flora.

Influence of Foliar Application of Zinc on Growth and Yield in Different Varieties of Rice (Oryza sativa L.) and Yield Validation Using SPSS Model

Agronomy Department, Farm, Sam Higginbottom University of Agriculture, Technology, and Sciences, Prayagraj (U.P.), India. to research the effects of zinc treatment on rice (Oryza sativa L.) growth and yield. The medications include the verities MTU-7029, BPT -5204, and RNR15048, as well as zinc concentrations of 0.2%, 0.3%, and 0.4%. The pH of the soil in the experimental plot was 7.8, the texture was sandy loamy, and the amount of organic carbon was low (0.35%). The larger plant height (117.68 cm), greater number of tillers per hill (13.64), Application of RNR-15048 + ZnSo4 - 0.4% significantly increased plant dry weight (55.47 g/plant), number of panicles/hill (10.01), number of grains/panicle (141.37), 1000 seed weight (22.27 gm), grain yield (6.43 t/ha), and stove yield (12.11 t/ha). Higher B:C ratio (2.37) and higher gross return (INR 1,52,860/ha), net return (INR 1,07,531/ha), and net return (INR 1,07,531/ha) were also noted in treatment-9 (RNR-15048 + ZnSo4 - 0.4%).

Resposta de genótipos de Urochloa mosambicensis à adubação fosfatada em solo com baixo nível de fósforo

Abstract Phosphorus (P) is one of the main nutrients capable of increasing yields of tropical grasses. The definition of adequate P fertilizer rates can contribute to improving forage production of pastures. However, the efficiency in the response of different genotypes of Urochloa mosambicensis (Hack.) Dandy (Bushveld herringbone grass) to P fertilizer rates is not known. This study aimed to quantify the response of U. mosambicensis genotypes to P fertilizer levels and classify the genotypes as to efficiency and responsiveness. The experiment was carried out in pots, under controlled conditions, in a completely randomized design, in a 2 x 9 factorial with five replications. The factors consisted of equivalent P rates of 10 and 90 kg ha-1 of P2O5 (triple superphosphate) and eight genotypes of U. mosambicensis (UmCO-1 (2), UmCO-2 (2), UmCO-4 (1), UmCO-8 (1), UmCO-11 (2), UmCO-12 (2), UmCO-13 (2) and UmCO-14 (2)), in addition to a control, Urochloa brizantha syn. Brachiaria brizantha cv. BRS Piatã. Each experimental unit consisted of one pot. Biometric attributes and dry mass yield were evaluated over four cutting cycles. There was no effect of the P fertilization x genotypes interaction for the variables evaluated. However, the highest fertilizer rate increased dry mass yield and tiller population density in all genotypes and cuttings evaluated. The genotype UmCO-4 (1) and the cultivar BRS Piatã proved to be responsive to and efficient in P use. The highest P rate promoted greatest production of dry mass and greatest number of tillers in all genotypes of U. mosambicensis.

Tillering dynamics in spring and summer of marandu palisade grass pastures previously used under deferred grazing

ABSTRACT This work was conducted to evaluate the effect of deferred pasture condition of Brachiaria brizantha cv. Marandu in the late winter on tillering during the growing season. The treatments were three pasture conditions at late winter: short pasture, tall pasture and tall/mown pasture. In September and October, tiller appearance rate (TApR) and tiller mortality rate (TMoR) were greater in the tall/mown pasture. In November and December, tall pasture presented greater TApR. From November to January the TMoR was greater in the tall pasture. The tiller stability index of short and tall/mown pastures were greater in October. The short pasture presented a greater tiller number than the tall and tall/mown pastures during the entire experimental period. Deferred and short pasture of marandu palisade grass at late winter presents in general lower tiller mortality and higher population density of tillers from the early spring onwards, in comparison to tall pasture. The mowing of marandu palisade grass with high forage mass at the late winter, although it only temporarily compromises the population stability of tillers, also stimulates its fast tillering from spring on.

Correlation and path analysis in wheat cultivars in the initial period of development

The cultivation of soybeans in the central region of the state of Rio Grande do Sul, has increased the interest of farmers for winter crops in the region. However, information related to crop development in a low-latitude environment is limited and necessary to improve crop management. The objectives of this article were to evaluate the linear relation between traits of spring wheat cultivars in the initial period of development in a low-altitude site. The experiments were conducted in two years in Santa Maria - RS. The experimental design used was randomized blocks, with ten wheat cultivars. The evaluations were carried out at the end of the tillering, where 300 plants were selected per year, obtaining a total sample number of 600 plants. After selecting, the character’s plant height (PH), the number of leaves of the main stem (NLMS), the number of leaves per plant (NLP), the number of tillers (NT), and the dry matter (DM) were measured. Pearson’s correlation coefficient matrices were estimated, and the path analysis of the main variable DM was performed as a function of PH, NLMS, NLP, NT, and DM. The cultivars TBIO Mestre and TBIO Sinuelo have a higher number of tillers. The NLP has a greater direct effect on DM, in field conditions it is recommended to count the NT, as it has a direct relationship with DM and NLP, associated with this, the character is fast to count and has agronomic value for the wheat crop. In a low-altitude cultivation site, the number of tillers depends on cultivation and environmental conditions. The cultivars TBIO Mestre and TBIO Sinuelo have high tillering capacity. Based on linear relationships, through the non-destructive selection of wheat plants with a greater number of leaves per plant and a greater number of tillers, plants with a higher dry matter mass are indirectly selected. However, the number of tillers is recommended because it is quick to measure.

Tillage and nitrogen managements increased wheat yield through promoting vigor growth and production of tillers

AbstractAdopting suitable tillage and fertilization technologies for wheat (Triticum aestivum L.) can address poor soil conditions and high residual nitrogen following rice (Oryza sativa L.) harvest to improve the sustainability of rice–wheat rotation systems. A field experiment was conducted in 2016–2018 to investigate the influence of tillage methods and nitrogen rates on wheat seedling growth (at the beginning of over‐wintering stage), tillering characteristics, and grain yield. The tillage methods included no‐tillage (NT), rotary tillage twice (RR), and plow tillage followed by rotary tillage (PR). The nitrogen rates were 270 (N270), 240 (N240), and 210 kg ha−1 (N210). In 2016–2017 (higher soil moisture during tillage), NT improved early growth (i.e., leaf area and biomass per stem), single spike yield, and grain yield compared with PR and RR. In 2017–2018 (lower soil moisture during tillage), PR and RR resulted in stronger seedlings (greater tiller number and leaf area and biomass per stem), more fertile tillers, and higher grain yield than NT. In both years, grain yield under RR was between that of PR and NT. With reduced nitrogen application, seedling growth, tiller number, single spike yield, and grain yield showed a declining tendency. We found that more tillers at seedling growth stage (the five‐leaf stage in both years) could boost fertile tiller number, and at this time greater leaf area and biomass per stem were correlated with higher single spike yield. This study demonstrates that suitable tillage and fertilizer applications can facilitate yield formation through improved number and vigor of the early‐produced tillers.

English

The effects of cassava/legume intercrop-rice relay and weed management practices on weed infestation, growth and yield of rice were investigated at Badeggi, Southern Guinea Savanna of Nigeria in 2011 to 2013 cropping seasons. The treatments consisted of factorial combination of cassava (IIT 427) intercrop with: Mucuna or Velvet bean [Mucuna pruriens (L.) DC.], Cowpea [Vigna unguiculata (L.) Walp.], Soybean [Glycine max (L.) Merr.], Hyacinth bean [Lablab purpureus (L.) Sweet.] and Porcupine Jointvetch (Aeschynomene histrix Poir.) and weed management practices: (i) application of propanil at 1.44 kg a.i ha-1 plus 2,4-D at 0.80 kg a.i ha-1 (Orizo Plus®) at the rate of 2.24 kg a.i ha-1 at three weeks after transplanting (WAT) rice followed by hoeing at 6 WAT, (ii) two hoeing at 3 and 6 WAT, (iii) one hoeing at 3 WAT, and (iv) weedy check with sole cassava and natural fallow as control laid in a split plot arranged in a randomized complete block with three replications. Across cassava/legumes intercrops, cassava/mucuna had lower weed density and dry matter, cassava/Aeschynomene and cassava/cowpea produced comparable taller rice plants, more rice panicles and paddy yield, and cassava/Aeschynomene produced greater number of rice tillers. Irrespective of the weed management practices, two hoeing at 3 and 6 WAT gave better weed control, taller rice plants, greater number of tillers and panicles, and higher paddy yield comparable to application of Orizo Plus® at 3 WAT followed by one hoeing at 6 WAT. This study suggests that sustainable weed control with Mucuna intercrop and rice productivity with Aeschynomene and cowpea intercrops can be achieved with two hoeing at 3 and 6 WAT or application of Orizo Plus® at 3 WAT followed by hoeing at 6 WAT in this agro-ecology of Nigeria. Key words: Intercrops, legumes, Oryza sativa L., paddy yield, weed suppression. &nbsp

Potential of upland rice yield based on tillers and leaf area on various organic matter as the observation variables

The potential of upland rice production can be described through the parameters of the number of tillers and flag leaf area. This is supported on the optimal number of tillers forming the basis for grain formation, while the flag leaf area is an illustration of the potential assimilation that plants can produce. Provision of organic material in dry land is an alternative to increase the availability of ground water. The aim of this research was to study the relationship between variables, those were number of tillers, flag leaf area and grain production. The experimental method used was a Randomized Block Design (RBD) with 2 factors. Upland rice varieties were be the first factor, namely IPB 9G, IPB 8G, Sigambiri Merah, and Situ Patenggang. The second factor was organic materials: solid decanter, filter mud, oil palm empty fruit bunches, oil palm fibre, and cow manure. The results showed that upland rice had a greater number of tillers and wider leaves would produce higher production per plot. The provision of solid decanter could increase the number of tillers (51.56%), flag leaf area (35%), grain production per plot (55.12%) compared to the treatments without the provision of organic matter.

Produção e morfogênese de capim BRS Tamani sob diferentes doses de nitrogênio e intensidades de desfolhação

The objective of this work was to evaluate the forage production, and the morphogenic and structural characteristics of Panicum maximum cv. BRS Tamani, as a function of nitrogen doses and cut intensities. The experiment was conducted under greenhouse conditions. Four nitrogen doses (0, 50, 100 and 200 mg/dm³) and two cut intensities (5 cm and 15 cm) were evaluated in a 4x2 factorial in a completely randomized design with four replicates. The leaf elongation rate of the Tamani grass was influenced by nitrogen fertilization, with a linear and positive response. No effect of defoliation intensity was observed for this variable. The leaf life had a negative linear influence of the nitrogen fertilization without effect of the defoliation intensity. The morphogenic characteristics of the Tamani grass are influenced by nitrogen fertilization. Plants with greater nitrogen supply lengthen more leaves, with a shorter appearance interval. In absence of nitrogen fertilization the BRS Tamani grass keeps the leaves alive longer and in smaller numbers. More intensely cut BRS Tamani grass plants have a greater number of tillers. Nitrogen fertilization increased forage yield of BRS tamani grass, with no effect on root production. Plants submitted to more intense cuts (5 cm) presented greater dry matter production of the aerial part.

Performance of dry matter yield and its components in germoplasm of alfalfa (Medicago sativa L.)

Se evaluó el comportamiento productivo en 100 familias de medios hermanos (FMH) derivadas de las variedades San Miguel y Oaxaca, y las poblaciones San Miguel x Oaxaca y Oaxaca x San Miguel, en macetas a la intemperie en Montecillo, Texcoco, Estado de México. Se realizaron cortes cada cinco semanas en otoño-invierno 2013-2014 y cada cuatro semanas en primavera 2014. Las FMH derivadas de San Miguel x Oaxaca y Oaxaca x San Miguel tuvieron en promedio 10 % mayor rendimiento de materia seca (RMS), tasa absoluta de crecimiento (TAC) y relación hoja:tallo (H:T) por planta, que las FMH derivadas de San Miguel y Oaxaca, en cada corte y estación del año. Las FMH derivadas de San Miguel presentaron mayor número de tallos (NT) en invierno y primavera, y menor altura de planta (AP) en primavera que las de Oaxaca y las FMH derivadas de San Miguel x Oaxaca y Oaxaca Revista Mexicana de x San Miguel. El RMS y TAC en primavera fueron 57 y 33 % más altos que en otoño e invierno. La relación H:T en otoño fue 5 % mayor que en invierno y 30 % mayor que en primavera; el mayor NT y AP se presentaron en primavera. La eficiencia en el uso de la radiación (EUR) fue mayor en primavera que en otoño e invierno con los valores más altos en abril. La variabilidad entre las FMH derivadas de San Miguel x Oaxaca y Oaxaca x San Miguel, indica la posibilidad de seleccionar familias superiores en rendimiento de materia seca.

Phenotypic analysis of a dwarf and deformed flower3 (ddf3) mutant in rice (Oryza sativa L.) and characterization of candidate genes

Abstracts Dwarf mutants are the crucial resources for molecular biology research and rice breeding. Here, a rice mutant, dwarf and deformed flower3 (ddf3), was identified in tissue culture of Oryza sativa cv. Dongjin. Compared with wild type, the ddf3 mutant exhibited severe dwarfism, a greater number of tillers and significantly decreased fertility. In addition, leaf length, panicle length, and grain length, were significantly shorter. All internodes of ddf3 were shorter than those of wild type, and histological analysis revealed that internode cell elongation was significantly inhibited in ddf3. In the ddf3 mutant, pollen activity was significantly decreased, and the development of most stigmas was abnormal. Genetic analysis indicated that the ddf3 mutant phenotypes are controlled by a single or tightly linked nuclear genes. Using an F2 mapping population generated from a cross between ddf3 and Yangdao 6 (9311), the DDF3 gene was mapped to a 45.21-kb region between insertion-deletion (InDel) markers M15 and M16 on the long arm of chromosome 7. Sequencing revealed a 13.98-kb-deletion in this region in the ddf3 mutant genome that resulted in the complete or partial deletion of ZF (DHHC type zinc finger protein), EP (expressed protein), and FH2 (actin-binding FH2 domain-containing protein) genes. Quantitative RT-PCR analyses revealed that in wild type, the transcript levels of FH2 were almost the same in all organs, while ZF was mainly expressed in the panicle, and no expression of EP was detected in any organ. Based on these results, ZF and FH2 could be potential DDF3 candidate genes involved in the regulation of rice morphology and flower organ development. Our work has laid the foundation for future functional analysis of these candidate genes and has provided a profitable gene resource for rice breeding for increased fertility in the future.

Improving grain yields on a sodic clay soil in a temperate, medium-rainfall cropping environment

Soil constraints are a major limitation to grain production on waterlogging-prone sodic soils in the medium-rainfall zone of southern Australia, and several options have been proposed to overcome these constraints. A field experiment commenced in 1999 to compare the effectiveness of different management strategies, including improved crop nutrition, soil amelioration by using gypsum with or without deep ripping, applying organic matter, using raised beds or delayed sowing on improving the growth and grain yields of four consecutive crops including wheat (Triticum aestivum) in 1999 and 2002, barley (Hordeum vulgare) in 2000, and faba beans (Vicia faba) in 2001. Improving crop nutrition alone generally did not significantly improve grain yields, whereas adding ameliorants such as composted pig bedding–litter or deep ripping + gypsum produced grain yield increases in all crops by up to 48% compared with the control. Similar increases in grain yields were produced when crops were grown on raised beds, even in seasons when growing-season rainfall was well below average. Greatest yield increases were recorded when both raised beds and ameliorants were used (up to 2 t/ha, or 63%). Spring-sown crops consistently produced lower grain yields than the (autumn-sown) control. For the three cereal crops (two wheat and one barley), increases in grain yields resulting from soil amelioration generally were not associated with increased harvest index or kernel size but were associated with greater tiller number and number of grains per m2. For the pulse crop, faba beans, yield increases were associated with greater dry matter production and increased number of grains per m2. All management strategies significantly increased crop nitrogen (N) uptake, although this did not necessarily translate to increased grain protein because of a dilution effect in the highest yielding treatments. Increases in grain yield coincided with improved root growth throughout the profile (up to 140 cm depth). All physical amelioration treatments either reduced the degree of temporary waterlogging, as indicated by shallow piezometers, or improved soil structure, as indicated by reduced cone penetrometer resistance, compared with the control. Reduction in soil exchangeable sodium percentage on this highly sodic clay soil, measured within the first season after implementation, was less clear-cut. Increases in grain yield, however, appeared related to improved N supply rather than greater water use. Large increases in grain yields across a range of seasonal conditions appear possible on these soil types in medium-rainfall environments provided both soil structure and nutrition are improved.

Salinity Effects on Germination, Growth, Photosynthesis, and Ion Accumulation in Wild Miscanthus sinensis Anderss. Populations

ABSTRACTThe lignocellulosic crop Miscanthus spp. has been identified as a good candidate for biomass production. To satisfy the need for high yield and to avoid competition with food production by growing the crop in marginal areas, we studied the responses of M. sinensis to salinity. Effects of salt concentrations (0−360 mM NaCl) on seed germination, growth, photosynthesis, and shoot ion accumulation were examined. In the germination test of 17 accessions, high salt concentration inhibited seed germination in all accessions, while germination percentage varied significantly among the accessions. Two accessions showing variable salt tolerance, JM0119 (salt‐tolerant) and JM0099 (salt‐sensitive), were selected for a greenhouse study on plant dry weight, leaf chlorophyll content, total leaf area, tiller number, photosynthetic rate (A), stomatal conductance (gs), photosystem‐II (PSII) operating efficiency (∆F/F´m), and shoot ion concentration during various lengths of time. The experiment was performed twice, but for most parameters, no significant differences between runs were observed. Salinity resulted in a reduction of plant growth. Photosynthetic rate and gs were adversely affected by all salt treatment levels, while ∆F/F´m was not reduced until salt concentrations reached 120 mM NaCl. In contrast to the increases of shoot Na+ and Cl− concentrations, shoot K+ concentration declined in the presence of salt. Overall, this study revealed a great variability for salt tolerance in M. sinensis germplasm. The relative advantage of JM0119 over JM0099 under saline conditions was primarily associated with larger leaf area, a greater number of tillers, greater photosynthetic capacity, and restricted Na+ accumulation in shoots.

Effect of water regime and nitrogen on growth, productivity and economics of summer rice varieties

The results of field experiment conducted during summer season of 2004 and 2005 showed that continuous field saturation increased plant height, tillers production, LAI, DMA, CGR, panicle and grain production, and test weight that ultimately produced high grain (6025 kg ha−1) and straw yield (6296 kg ha−1) with high harvest index, gross return and net return. IR-36 recorded higher number of tillers m−2, LAI, DMA, CGR, greater number of panicles m−2 and test weight and finally produced higher grain (5671 kg ha−1) and straw (6001 kg ha−1) yields and paid greater gross and net return than those of Annapurna. The crop receiving 120 kg N ha−1 (RDN) increased plant height, tiller production, LAI, DMA, CGR, recorded higher number of panicles m−2 and grains panicle−1 and produced higher grain and straw yield with higher return. The crop at continuous saturation with RDN recorded greater tiller production, LAI and CGR during reproductive period over most of the other treatment combinations. It increased panicle and grain production and produced the highest grain (6299 kg ha−1) yield and paid very high net return (` 16818 ha−1) from summer rice. IR 36 receiving RDN produced greater number of tillers m−2, LAI and CGR during reproductive period, recorded the higher number of panicles m−2 and grains panicle−1 and produced the highest grain yield (5882 kg ha−1) of summer rice over most of the other treatments. IR 36 at continuous saturation with RDN improved growth attributes, increased yield components, produced high grain yield and paid high net return under the study.

Biomass and Molecular Characteristics of Multi-tillering Miscanthus Mutants

Compared to wide ranges of genetic variation of natural populations, very limited Miscanthus cultivar has been released. This study was the first report on the development of Miscanthus cultivar by means of radiation breeding. Seeds of M. sinensis were initially exposed to gamma rays of 250 Gy for 24 h, generated from a <TEX>$^{60}Co$</TEX> gamma-irradiator. The irradiated seeds were sown and then the highly tiller-producing mutants were selected for this study. Biomass-related parameters including tiller number, plant height, stem diameter, and leaf number were measured. Ploidy level and internal transcribed spacer (ITS) were investigated to characterize the mutants compared to wild type (WT) Miscanthus. Plant height and tiller number were negatively related, where multi-tillering mutants were relatively short after 4 month growth. However stem diameter and leaf number were greater in mutants. All the materials used in this study were diploid, implying that the mutants with greater tiller numbers and stem diameter were not likely related to polyploidization. Based on the sequence of ITS regions, the mutants demonstrated base changes from the gamma irradiation where G+C content (%) was decreased in the ITS1, but increased in ITS2 when compared to WT sequence. ITS2 region was more variable than in ITS1 in the mutants, which collectively allows identification of the mutants from WT. Those mutants having enhanced tillers and allelic variations might be used as breeding materials for enhanced biomass-producing Miscanthus cultivars.

Estimating Crop Coefficient in Intermittent Irrigation Paddy Fields Using Excel Solver

The current study proposes a novel method using Excel Solver to estimate, from limited data, crop coefficient (Kc) in paddy fields under intermittent irrigation (II). The proposed method was examined in a field experiment conducted at Karang Sari Village, Bekasi, West Java, Indonesia during the first rice season of 2007/2008 (December 2007 to April 2008) in the rainy season. As the control, continuous flooding irrigation (CF) was applied to the conventional rice cultivation fields. Based on the observed water storage, Excel Solver was used to estimate crop evapotranspiration. Estimated crop evapotranspiration was used to compute Kc value, then the average Kc values at each growth stage were compared with that for the CF treatment. The estimation method was evaluated by comparing estimated crop evapotranspiration and the crop evapotranspiration derived by the well established FAO procedure. Excel Solver estimated crop evapotranspiration accurately with R2 values higher than 0.81. Accordingly, more than 81% of the FAO crop evapotranspiration was described by the proposed method. Thus, Kc value could be well determined from those estimated crop evapotranspiration. Under the II treatment, the average Kc values were 0.70, 1.06, 1.24 and 1.22 for the initial, crop development, reproductive and late stages, respectively. These values were lower than those under the CF treatment for initial and crop development stages because of a minimal soil evaporation and intense dryness during these stages. However, average Kc values under the II treatment were higher than those under the CF treatment at the reproductive and late stages, indicating that the II treatment promoted more plant activity particularly for dry biomass production as indicated by a greater number of tillers per hill.

Evaluation of the performance of three varieties of upland rice in degraded acid soil in Abakaliki, Ebonyi State, Nigeria

The performances of three different varieties of improved upland rice (ITA 257; EX-CHINA; ITA 315) were evaluated in a 2 year study under Abakaliki environmental condition. The design of the experiment was a randomized complete Block Design with 3 replications. ITA 315 and EX-China, on the average, had greater number of tillers than ITA 257. It was similarly observed that the yield was higher in ITA 315 and Ex-china than ITA 257 indicating that both ITA 315 and Ex-china perform better on the soil environment studied. It is recommended that the resource poor farmers adopt the production of ITA 315. Keywords : upland rice, degraded acid soil, Abakaliki Journal of Technology and Education in Nigeria Vol. 9(2) 2004: 1-7