Row Length Research Articles

The Resistance of Exotic Wheat Germplasm to Stripe Rust (Puccinia striiformis f. sp. tritici) under Nature Infection at Dera Ismail Khan, Pakistan

An experiment comprising of 49 exotic wheat germ plasm accessions was conducted at AridZone Research Institute, Dera Ismail Khan, Pakistan under rainfed condition during 2013-14 for theirresistance against stripe rust disease. The trial was laid out in randomised complete block design with threereplications. All entries were planted in a four-row plot with 3 m for row length and 25 cm for space amongrows. A local susceptible check was repeatedly sown after every 10 test entries. The crop was maintainedunder rainfed conditions. Results revealed that all the exotic genotypes were genetically divergent inresponse to stripe rust disease. The disease score ranged from very highly susceptible to very highlyresistant. Among 49 exotic lines, 27 exhibited from very highly resistant while 10 were susceptible to veryhighly susceptible.

Setting the optimal length to be scanned in rows of vines by using mobile terrestrial laser scanners

Mapping the leaf area index (LAI) by using mobile terrestrial laser scanners (MTLS) is of significance for viticulture. LAI is related to plant vigour and foliar development being an important parameter for many agricultural practices. Since it may present spatial variability within vineyards, it is very interesting monitoring it in an objective repeatable way. Considering the possibility of using on-the-go sensors such as MTLS within an agricultural plot, it is necessary to set a proper length of the row to be scanned at each sample point for a reliable operation of the scanner. Three different row length sections of 0.5, 1, and 2 m have been tested. Data analysis has shown that models required to estimate LAI differ significantly depending on the scanned length of the row; the model required to estimate LAI for short sections (0.5 m) is different from that required for longer sections (1 and 2 m). Of the two models obtained, we recommend using MTLS for scanning row length sections of 1 m because the practical use of the sensor in the field is simplified without compromising the results (there is little variation in the model when the row length section changes from 1 to 2 m). In addition, a sufficient number of sampling points is obtained to support a map of the LAI. Linear regression models using as explanatory variable the tree area index, obtained from the data provided by the scanner, are used to estimate the LAI.

The effect of row grade and length on soil erosion from concentrated flow in furrows of contouring ridge systems

Concentrated flow in furrows may lead to serious rill erosion in production systems where ridges are mulched with plastic film in contouring ridges. Studying the effect of influential factors on soil erosion in such systems could improve our understanding on erosion process and take appropriate control treatments. Considering a furrow with mulched ridges on both sides as a width-limited eroding rill, an in situ field experiment was conducted to analyze the effect of row grades and row lengths on soil erosion. Soil erosion indices, including runoff, runoff modulus, sediment concentration, soil loss, and soil loss modulus were monitored. Row grade and length exerted significant effect on all indices at p<0.01. The relationship of sediment concentration, soil loss, soil loss modulus and row grade could be fitted by exponential functions (R2>0.950, p<0.01) with the exponents expressed as second-order polynomial functions. From the convex curves of these exponential functions, the critical row grade at which the maximum values occurred were interpreted as 10%. With row grade increasing, erosion presented a detachment-limited process. The relationship between row length and soil erosion indices could be modeled by different exponential functions (R2>0.830, p<0.01): two-parameter exponential function for runoff, modulus of runoff and modulus of soil loss; Box Lucas model for sediment concentration; and second-order polynomial function for soil loss. Based on the results, we suggest that avoiding the row grade of 10% and row length <5m could reduce soil loss in the contouring ridges where plastic film covers ridges and irrigation is used to supply water into furrows.

High productivity of wheat intercropped with maize is associated with plant architectural responses

Mixed cultivation of crops often results in increased production per unit land area, but the underlying mechanisms are poorly understood. Plants in intercrops grow differently from plants in single crops; however, no study has shown the association between plant plastic responses and the yield advantage. Here, we assessed the productivity of wheat-maize intercropping as compared to sole wheat and sole maize, and the associated differences in wheat shoot and leaf traits. In two field experiments, intercrop wheat and maize were both grown in alternating strips consisting of six rows of wheat and two rows of maize. The traits of wheat plants in border rows of the strips were compared to the traits of plants in the inner rows as well as those in sole wheat. Leaf development, chlorophyll concentration and azimuth, as well as the final leaf and ear sizes, tiller dynamics of wheat and yield components of both crops were determined. The relative densities of wheat and maize in the intercrop were 0.33 and 0.67, respectively, but the corresponding relative yields compared to the respective monocultures were 0.46 for wheat and 0.77 for maize. Compared to wheat plants in the inner rows of the intercrop strips as well as in the monoculture, border-row wheat plants in the intercrop strips had (a) more tillers owing to increased tiller production and survival, and thus more ears, (b) larger top leaves on the main stem and tillers, (c) higher chlorophyll concentration in leaves, (d) greater number of kernels per ear and (e) smaller thousand-grain weight. Grain yield per metre row length of border-row wheat was 141% higher than the sole wheat, and was 176% higher than the inner-row wheat. The results demonstrate the importance of plasticity in architectural traits for yield advantage in multispecies cropping systems.

Versatile Strip Seed Drill: A 2-Wheel Tractor-Based Option for Smallholders to Implement Conservation Agriculture in Asia and Africa

Smallholders in Asia and Africa require low-cost seed drills for minimal soil disturbance while establishing various crops. A seed drill that can be drawn by the widely-available two-wheel tractor (2WT) is an attractive option for mechanization of no-till in small-sized fields. The Versatile Strip Seed Drill (VSSD) was designed with the capacity to make up to 40 mm wide and 60 mm deep strips in untilled land along with seed and basal fertilizer application in a single-pass operation, while powered by the 8.95 to 11.93 kW 2WT. An important innovation of the VSSD was to fit the seed box with both fluted roller-type seed meters for delivery of sufficient small-size seeds to achieve adequate plant density per unit row length; and vertical disk-type seed meters for precision and spaced row planting of larger seeds. Both incessant seed dropping by fluted roller seed meters and spaced planting by vertical disk type seed meters provided optimum plant populations that were generally higher than in conventional, full-tillage plots with the same rate of hand broadcasted seed and fertilizers. Time required for crop establishment by VSSD ranged from 0.13 to 0.18 ha·h−1. When the VSSD was attached to the 2WT for crop establishment, the diesel fuel consumption varied from 4.4 to 6.1 L·ha−1, which was lower than for most 2WT-based planters previously used in Bangladesh. In on-farm multi-locations trials, wheat crops established with the VSSD had statistically similar grain yield compared to conventional tillage; however, significantly higher grain yield was obtained from mustard and lentil, by 14% and 19%, respectively. The VSSD is a unique, minimum-soil-disturbance multi-crop planter, and can be a platform on which to build conservation agriculture systems for small farms in Asia and Africa.

Effect of Plant Spacing on Yield and Yield Attributes of Maize Hybrids

The study was conducted at experimental fields of the Krishi Vigyan Kendra, Kapurthala. The experiment was laid out in a 6 strip plots with plot size of 48 m2 including 2 hybrids (PMH 1 and DKC 9125) at 3 plant population densities comprising of 55, 555, 83, 333 and 1, 11, 111 plants/ha with the objective of observing the effect of plant spacing on yield attributes and yield of maize hybrids. The yield attributing factors as number of rows per cob, number of grains per row, cob girth and cob length were determined and finally the yield was recorded for both the hybrids. In case of DKC 9125 the only factor contributing to increase in cob yield and grain yield per unit area was the number of plants grown in the area, so the maximum yield was obtained at 15 cm plant spacing whereas, in case of PMH 1, both yield attributing factors (cob length and plant spacing) ultimately led to increase in grain yield. At 20 cm plant spacing the number of plants were reduced but increase in cob length at wider plant spacing nullified the effect of lesser plants grown per unit area. It was due to the reason that increase in cob length did not occur proportionately to the reduction in plant population. Hence, PMH 1 hybrid gave maximum cob yield and grain yield at 20 cm plant spacing.

Effects of weed control treatments on wheat crop and associated weeds

A field experiment was conducted in wheat during Rabi season 2011-12 on sandy loam soil at Crop Research Centre, Chirodi of Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut (U.P.).The experiment was conducted in R.B.D. with three replications comprising ten treatments of weed management, clodinafop 60 g a.i ha -1 , sulfosulfuron 25 g a.i ha -1 , metribuzin at 105 g a.i ha-1, carfentrazone 40 g ai ha -1 , clodi.+ metri 60 + 122.5 g a.i ha -1 , clodi. + metri 60 + 105 g a.i ha -1 , sulfo. +metri 25 + 105 g a.i ha -1 , sulfo. + carfen. 25 + 40 g a.i ha -1 as post emergence and weed free and weedy. The results indicated that plant population, plants height, maximum number of tillers/meter row length, dry matter accumulation, highest grain yield (55.13 q/ha -1 ), straw yield (78.08 q/ha -1 ) significantly reduced the weed population, dry weight of weed, highest weed control efficiency and minimum loss of nutrient were recorded with the application of sulfosulfuron .+metribuzin 25 + 105 g a.i ha -1 as post emergence established its superiority over rest of the herbicides. Similarly application of sulfosulfuron .+metribuzin 25 + 105 g a.i ha -1 as post emergence resulted into higher gross return (Rs. 90362.05), net return (Rs. 63453.59 ha -1 ) and B: C ratio (2.48).

Production components of corn as function of seed distribution along the planting row

ABSTRACT High corn yields in high-tech systems are related to proper crop implementation. This study aimed to evaluate the effects of variability in the distribution of seeds along the planting row on corn production components. The study was conducted under Cerrado conditions in the municipality of Urutaí, GO, Brazil. The experimental design was randomized blocks in a 5 x 2 factorial scheme, with four replicates. The effects of five coefficients of variation (0, 20, 40, 60 and 80%) of non-uniformity in the spatial distribution of seeds along the planting row of two corn hybrids (P30F53HX and P3646HX) were evaluated. No interactions were observed for the analysed corn variables. However, as the non-uniformity in seed distribution along the planting row increased, stalk diameter, hundred-grain weight, number of rows per ear, number of kernels per row and ear length decreased. Additionally, linear reductions were observed in corn grain yield with the increase in the coefficient of variation of the spatial distribution of seeds along the planting row. Between the hybrids, the 30F53HX showed higher hundred-grain weight.

Comparative Effects of Biogeography, Ecology and Radiation on Morphology of Some Cranial Variables in Raccoon Dogs Species (Nyctereutes procyonoides)

The present adimension in tropicalN. procyonoides. Comparable archi- tecture and construction was found in mandibular height at M1 as well as Koronium to angular process length, cheek tooth row length diverged widely across geographic locations being highest and lowest in Polish and tropical species re- spectively. Divergence also occurred in rostral and caudal viscero-cranial lengths, a similarity in the latter parameter between Ussuriensis and subject of this survey was observed. Maximum palatal length was lowest in Ussuriensis and highest in tropical species. The study concludes that origin, possible genetic distance, period of radiation and human activities impacted on changing skull parameters. Main- land species from Japan appears smaller sized compared to island versions. Newer geographic areas of introduction of this species demonstrated an up-regulation in some cranial parameters.

Simultaneous large deviations for the shape of Young diagrams associated with random words

We investigate the large deviations of the shape of the random RSK Young diagrams associated with a random word of size $n$ whose letters are independently drawn from an alphabet of size $m=m(n)$. When the letters are drawn uniformly and when both $n$ and $m$ converge together to infinity, $m$ not growing too fast with respect to $n$, the large deviations of the shape of the Young diagrams are shown to be the same as that of the spectrum of the traceless GUE. In the non-uniform case, a control of both highest probabilities will ensure that the length of the top row of the diagram satisfies a large deviation principle. In either case, both speeds and rate functions are identified. To complete our study, non-asymptotic concentration bounds for the length of the top row of the diagrams, that is, for the length of the longest increasing subsequence of the random word are also given for both models.

A hybrid format for better performance of sparse matrix-vector multiplication on a GPU

In this paper, we present a new sparse matrix data format that leads to improved memory coalescing and more efficient sparse matrix-vector multiplication for a wide range of problems on high-throughput architectures such as a GPU. The sparse matrix structure is constructed by sorting the rows based on the row length (defined as the number of non-zero elements in a matrix row) followed by a partition into two ranges, short rows and long rows. Based on this partition, the matrix entries are then transformed into ELLPACK or vectorized compressed sparse row format. In addition, the number of threads are adaptively selected by their row length, in order to balance the workload for each graphics processing unit thread. Several computational experiments are presented to support this approach and the results suggest a notable improvement over a wide range of matrix structures.

Effect of irrigation and nitrogen levels on forage yield and quality of pearl millet [Pennisetum glaucum (L.) R.Br.

An experiment was conducted to study the effect of irrigation and nitrogen on pearl millet during summer 2010 at Anand Agricultural University, Anand. Twelve treatment combinations of four irrigation levels (0.4, 0.6, 0.8 and 1.0 IW: CPE ratio), three levels of nitrogen (80, 120 and 160 kg N ha -1 ) were tested in split plot design with four replications. The result revealed that the frequent irrigations at 1.0 IW : CPE ratio significantly increased the plant height, tillers per meter row length and leaf : stem ratio and produced significantly the highest green forage, dry matter and crude protein yields and registered the highest net returns. However, lower irrigation level of 0.4 IW: CPE ratio was significantly superior in WUE than 1.0 IW : CPE ratio. Successive increase in nitrogen application increased yield attributes, leaf, stem ratio, crude protein content as well as WUE. Application of 160 kg N ha-1 recorded significantly the highest green forage, dry matter and crude protein yields of pearl millet and gave the highest net returns.

Response of weed management practices on the Productivity of urdbean (Vigna mungo L. Hepper)

A field Investigation was carried out to evaluate the effect of hand weedings and herbicides on the weed flora, growth and yield of urdbean (Vigna mungo). The experiment was conducted during kharif season 2011 in loamy sand soil, to study the effect of different Ten weed management treatments comprising weedy check, weed free, one hand weeding (HW) at 20 days after sowing (DAS), two HW at 20 and 40 DAS, trifluralin at 0.75 kg/ha, alachlor at 1.5 kg/ha, imazethapyr at 0.10 kg/ha, trifluralin at 0.75 kg/ha + HW at 30 DAS, alachlor at 1.5 kg/ha + HWat 30 DAS and imazethapyr at 0.10 kg/ha + HW at 30 DAS on urdbean. Results showed that the maximum plant height was recorded under weed free treatment at all the growth stages and the maximum dry matter accumulation of 108.88 and 159.31 g per metre row length at 50 DAS and harvest stages was obtained under imazethapyr at 0.10 kg/ha + HW at 30 DAS treatment that was significantly higher by 17.8, 21.8, 24.6, 31.8 and 56.0 per cent at 50 DAS and 20.4, 17.6, 25.4, 29.0 and 50.1 per cent at harvest stage over imazethapyr at 0.10 kg/ha, one HW at 20 DAS, alachlor at 1.5 kg/ha, trifluralin at 0.75 kg/ha and weedy check treatments, respectively.. Application pre emergence application of imazethapyr at 0.10 kg/ha + HW at 30 DAS was found the most effective treatment with regard of grain yield (1403 kg/ha) and net returns (Rs 34815/ha). Two hand weedings done at 20 and 40 DAS also produced grain yield of 1392 kg/ha with net returns of Rs 33469 /ha.

Dynamic changes in bubble profile due to surfactant and tape orientation of emitters in drip tape during aerated water irrigation

Use of aerated water for drip irrigation using a pressure differential Venturi has been reported to produce positive response on crop yield and water use efficiency. We present two options for increasing the distance from the source of irrigation an air/water mixed phase travels. We discuss observed results for a row length of 500m of drip tape.The first option relates to the orientation of drip tape emitters to the ground plane. In the up orientation the emitters are on the top of the drip tape and in the down position the emitters are along the bottom of the drip tape. We found higher air void fraction with the emitters down, compared to the standard placement with the emitters up. We also discuss observations of field trials for this treatment.The second option explored two concentrations (2ppm and 4ppm) of BS1000™ surfactant in irrigation water in the drip tape. Bubble size decreased, whereas air void fraction increased along the length of drip tape, with increased concentration of surfactant, in both up and down emitter positions in the drip irrigation tape. The best result was using non-ionic surfactant at 4ppm with the emitter facing down where the bubble distribution and the availability of micro-bubbles over the 500m irrigation was greatest. This knowledge will be of benefit in drip and sub-surface drip irrigated agriculture.

Development of a telemetry and yield-mapping system of olive harvester.

Sensors, communication systems and geo-reference units are required to achieve an optimized management of agricultural inputs with respect to the economic and environmental aspects of olive groves. In this study, three commercial olive harvesters were tracked during two harvesting seasons in Spain and Chile using remote and autonomous equipment that was developed to determine their time efficiency and effective based on canopy shaking for fruit detachment. These harvesters work in intensive/high-density (HD) and super-high-density (SHD) olive orchards. A GNSS (Global Navigation Satellite System) and GSM (Global System for Mobile Communications) device was installed to track these harvesters. The GNSS receiver did not affect the driver’s work schedule. Time elements methodology was adapted to the remote data acquisition system. The effective field capacity and field efficiency were investigated. In addition, the field shape, row length, angle between headland alley and row, and row alley width were measured to determinate the optimum orchard design parameters value. The SHD olive harvester showed significant lower effective field capacity values when alley width was less than 4 m. In addition, a yield monitor was developed and installed on a traditional olive harvester to obtain a yield map from the harvested area. The hedge straddle harvester stood out for its highly effective field capacity; nevertheless, a higher field efficiency was provided by a non-integral lateral canopy shaker. All of the measured orchard parameters have influenced machinery yields, whether effective field capacity or field efficiency. A saving of 40% in effective field capacity was achieved with a reduction from 4 m or higher to 3.5 m in alley width for SHD olive harvester. A yield map was plotted using data that were acquired by a yield monitor, reflecting the yield gradient in spite of the larger differences between tree yields.

Effect of irrigation scheduling on the growth and yield of wheat genotypes

An investigation was carried out on the effect of irrigation schedules and genotypes on the growth and yield components of wheat (Triticum aestivum L.) at the University of Agricultural Sciences, Dharwad (Karnataka) in the year 2001-02. The design of the experiment was split plot with three replications. Irrigation schedules(I7) at crown root initiation + tillering + jointing + flowering + milky + dough stages recorded maximum effective tillers at harvest (94.66), total dry matter production (217.58 g m-1 row length), leaf area (49.31 dm2 m-1 row length), leaf area index (2.18), the mean ear length (6.89 cm), number of grains per ear (34.58), 1000 grain weight (39.83 g). Due to increased growth parameters, I7 irrigation schedule resulted in maximum grain yield (2669 kg ha-1) over I1 (1626 kg ha-1), I4 (2128 kg ha-1), I2 (2150 kg ha-1) and I3 (2240 kg ha-1) but was on par with I5 (2463 kg ha-1) and I6 (2580 kg ha-1). Significantly higher (2128 kg ha-1) grain yield was observed in I4 irrigation schedule over I1 (1626 kg ha-1) but was on par with I2 (2150 kg ha-1) and I3 (2240 kg ha-1) irrigation schedule. Significantly lowest (1626 kg ha-1) grain yield was recorded in irrigation schedule at crown root initiation and tillering stage. Among the wheat genotypes, DWR-1006 (durum wheat) recorded higher effective tillers at harvest (84.28), total dry matter production (206.06 g m-1 row length), leaf area (46.45 dm2 m-1 row length), leaf area index (2.06), number of grains per ear (33.46), 1000 grain weight (40.83 g), harvest index (0.379) and grain yield (2390 kg ha-1). The grain yield was affected due to wheat genotypes. Significantly higher (2390 kg ha-1) grain yield was recorded in wheat genotype DWR-1006 over DWR-162 (2140 kg ha-1).

Character association studies in pearl millet [Pennisetum glaucum(L.) R. Br.] for green fodder yield and related traits

A field experiment was carried out in pearl millet [Pennisetum glaucum (L.) R. Br.] with 30 genotypes including three check varieties, to study character association among characters related to green fodder yield, in RBD with three replications. The observations were recorded on individual plant basis for five randomly selected plants of each genotype for each replication for plant height, leaf length, leaf width, stem thickness, internode length and spike length. Days to 50% flowering, number of tillers per meter row length, dry matter per cent, dry matter yield, leaf area, leaf: stem ratio, and green fodder yield were observed on plot basis. Based on correlation, it was concluded that days to 50% flowering, plant height, number of tillers per meter row length, leaf: stem ratio, leaf length, leaf width, stem thickness, spike length, dry matter yield and leaf area were having positive and significant correlation with green fodder yield. Based on path coefficient analysis, it was concluded that dry matter yield, leaf area, plant height, leaf: stem ratio, number of tillers per meter row length and spike length were having high positive direct effect on green fodder yield. Thus, selection for these characters will be effective to improve green fodder yield in pearl millet.

Efficacy of newer insecticides and biorationals on larval population of green semilooper and tobacco caterpiller

The experimental findings revealed that larval population of green semilooper and Spodoptera litura per meter row length at 3, 7, and 10 days after spraying was low in thiamethoxam 25 WG 100 g/ha alternate with rynaxypyr 20 Sc @ 150 ml/ha followed by thiamethoxam 25 WG 100 g/ha alternated with triazophos 40 Ec @0.80 l/ha, thiamethoxam 25 WG 100 g/ha alternated with indoxacarb 15 Ec @ 0.50 l/ha and thiamethoxam 25 WG 100 g/ha alternated with spinosad 45 SC @ 0.20 l/ha as compared to untreated control. The significantly maximum grain yield was recorded in thiamethoxam 25 WG 100 g/ha alternated with triazophos 40 Ec @0.80 l/ha, 1481 kg/ha treated plots followed by thiamethoxam 25 WG 100 gm/ha alternated with rynaxpayr 20 Sc @ 150 ml/ha, 1376 kg/ha and thiamethoxam 25 WG 100 gm/ha alternated with spinosad 45 Sc @0.20 l/ha, 1262 kg/ha as compared to untreated control, 653 kg/ha. Application of thiamethoxam 25 WG 100 gm/ha alternated with triazophos 40 EC @ 0.80 l/ha, gave the benefit of Rs. 15,470.

Morpho-Physiological Responses of Wheat (Triticum aestivumL.) Genotypes under Late Sown Condition

Late sowing of wheat results in exposure to high temperature during reproductive phase (seed filling). The present paper studies the effects of late sown condition on various morphophysiological parameters at different stages of growth, in two wheat genotypes i.e., HUW-510 (high temperature resistant) and HUW-468 (high temperature sensitive). The three dates of sowing were 20th November (DOS I), 10th December (DOS II) and 30th December (DOS I). Leaf area (LA), number of leaves, net assimilation rate (NAR), crop growth rate (CGR), relative growth rate (RGR) and leaf area index (LAI) were higher in the early sown plants compared to late sown plants. The declining trend was found in LA and number of leaves at DOS III in HUW-468. NAR in both the genotypes increased slowly at the early stages of growth while it increased sharply at the later stages with fluctuations in most cases. Higher values of CGR were found in the early sown condition in HUW-468. LAI was highest in DOS I while higher reduction was observed under DOS III in both the genotypes. The number of ear per 20 cm row length, number of grains per ear, grain yield per plant, 1000 grain weight and harvest index were significantly higher in HUW-510 followed by HUW-468 under DOS I as compared to DOS III. Late sown condition significantly decreased various morpho-physiological responses and yield attributes in wheat, particularly, in case of high temperature sensitive genotype, HUW-468.

Matrix Polynomials, Similar Operators, and the Imaginary Axis Eigenvalues of a Matrix Delay Equation

We present a new approach to determining the imaginary axis eigenvalues of a matrix delay equation. With a full rank delay coefficient matrix, the approach requires computation of the generalized eigenvalues of a pair of matrices which are a quarter of the size used in currently known matrix-based or operator approaches. These matrices have square of $n$ for both row and column length, improved from twice those lengths, for an equation having matrix $n\times n$ coefficients with rank $n$ delay matrix. Considering problem dimension and computational demands, this brings matrix-based approaches more in synchrony with the well-known scalar substitution approach. Given the symmetries evident in our approach, problems previously done with computation alone can now be considered with insight, and sometimes completed with simple calculations. Some of the computational and mathematical features of the approach are displayed in a section of examples.