The effect of quadrat shape and placement on the accuracy of yield and density estimates for crops seeded in narrow rows

1995 ◽  
Vol 75 (4) ◽  
pp. 889-892
Author(s):  
Larry Hume ◽  
Scott Shirriff
Keyword(s):  
Key Words ◽  
Plant Density ◽  
Sampling Unit ◽  
Plant Populations ◽  
Density Estimates ◽  
Plot Size ◽  
Row Width

Small quadrats (commonly 1-m2 or less) have been used extensively as the sampling unit in studies examining crops seeded in narrow rows. The effects of sampling unit shape and orientation on yield and plant density estimates was examined. When small quadrats are required for sampling crops seeded in narrow rows, sampling would best be done using rectangular quadrats with sides parallel to crop rows and having some multiple of row width. In seventy seven published papers from 1988 to 1994, the quadrat shape used in sampling plant populations was appropriate in only fourteen instances. Inappropriately shaped quadrats could result in errors of up to 25% in estimates of crop related variables, such as yield. Key words: sampling unit, quadrat shape, plot size, plot shape

EFFECT OF CANOPY AND INCORPORATION ON METRIBUZIN PERSISTENCE IN SOILS

1989 ◽  
Vol 69 (3) ◽  
pp. 711-714 ◽  
Author(s):  
K. I. N. JENSEN ◽  
E. R. KIMBALL ◽  
J. A. IVANY
Keyword(s):  
Key Words ◽  
Half Life ◽  
Field Tests ◽  
Soil Surface ◽  
Bare Soil ◽  
Field Conditions ◽  
Row Width ◽  
Sampling Zone

The half-life of metribuzin applied to a bare soil surface was calculated to be 3–7 d over four field tests. An artificial cover erected after application or a shallow incorporation increased the half-life of metribuzin approximately 2.5- to 3-fold. Leaching out of the 0- to 5-cm-deep sampling zone could not account for loss of metribuzin. It was concluded that metribuzin persistence may be affected by volatility and/or photodecomposition losses under field conditions, especially shortly after application. Key words: Metribuzin half-life, volatility, photodecomposition, row width

scholarly journals PENGARUH JARAK TANAM DAN DOSIS PUPUK TERHADAP PRODUKSI DAN VIABILITAS BENIH SETEK NILAM (Pogostemon cablin Benth)

2020 ◽  
Vol 18 (2) ◽  
pp. 81
Author(s):  
SUKARMAN SUKARMAN
Keyword(s):  
Plant Growth ◽  
Key Words ◽  
Seed Quality ◽  
Plant Density ◽  
Plant Spacing ◽  
Experimental Station ◽  
Pogostemon Cablin ◽  
C Value ◽  
Plot Design

<p>ABSTRAK<br />Sampai saat ini informasi pengaruh jarak tanam dan dosis pupuk<br />terhadap produktivitas, dan viabilitas benih nilam (Pogostemon cablin<br />Benth) masih terbatas. Untuk itu penelitian ini dilakukan dengan tujuan<br />mendapatkan jarak tanam dan dosis pupuk yang optimum untuk produksi<br />benih/setek nilam. Penelitian dilakukan di Kebun Percobaan (KP)<br />Sukamulya, Balai Penelitian Tanaman Rempah dan Industri Lain (Balittri),<br />Pakuwon, Parungkuda, Sukabumi, dari Januari sampai November 2010.<br />Percobaan faktorial, dengan tiga faktor dan tiga ulangan, disusun dalam<br />rancangan petak terbagi dua kali (RPPT). Petak utama adalah dua varietas<br />nilam yaitu Sidikalang dan Lhokseumawe. Anak petak adalah tiga jarak<br />tanam yaitu (1) 1 x 0,5 m; (2) 1 x 0,7 m; dan (3) 1 x 1 m. Anak-anak petak<br />adalah dua dosis pemupukan yaitu : 1) 30 ton pupuk kandang, 300 kg urea,<br />150 kg SP-36, dan 300 kg KCl/th, dan 2) 45 ton pupuk kandang, 450 kg<br />urea, 225 kg SP-36, dan 450 kg KCl/th. Ukuran plot 8,4 x 5 m. Parameter<br />yang diamati adalah pertumbuhan tanaman (tinggi tanaman, jumlah<br />cabang primer, sekunder, dan tersier), produksi benih pertanaman,<br />diameter bagian pangkal, tengah, dan pucuk dari cabang primer dan<br />sekunder, kadar karbohidrat dan serat, dan viabilitas benih setek.<br />Pengamatan dilakukan pada umur enam bulan setelah tanam (6 BST).<br />Hasil penelitian menunjukkan bahwa : (1) varietas Sidikalang dengan<br />dosis pemupukan 45 ton pupuk kandang, 450 kg urea, 225 kg SP-36, dan<br />450 kg KCl/th, menghasilkan jumlah cabang primer paling tinggi yaitu<br />14,29; (2) jarak tanam 1 x 0,5 m menghasilkan benih setek tertinggi<br />(73.555 stek/1.000 m 2 ). Rata-rata diameter benih berasal dari pangkal ≥ 5<br />mm, sedangkan rata-rata diameter benih berasal dari pucuk ≥ 4 mm; (3)<br />Viabilitas benih pada 0 dan 4 hari setelah penyimpanan ≥ 80%. Jarak<br />tanam 1 x 0,5 m dengan dosis pupuk kandang sebanyak 30 ton, 300 kg<br />urea, 150 kg SP-36, dan 300 kg KCl pertahun merupakan dosis yang<br />optimal untuk produksi benih/setek nilam. Kombinasi perlakuan<br />pemupukan 30 ton pupuk kandang, 300 kg urea, 150 kg SP-36, 300 kg<br />KCl/th dengan jarak tanam 1 x 0,5 m menghasilkan keuntungan tertinggi<br />yaitu: Rp 6.668.500 dengan nilai B/C 2,05.<br />Kata kunci : Pogostemon cablin Benth, jarak tanam, pemupukan,<br />produksi, kualitas benih/setek</p><p>ABSTRACT<br />Effect of Spacing and Fertilizer Dosages on Production<br />and Viability of Patchouli Cutting Seeds<br />Information on the effect of plant density and fertilizer dosage on<br />the production and viability of patchouli seeds is still limited. This<br />experiment was aimed at finding out optimum plant spacing and fertilizer<br />dosage for improving production and quality of patchouli cutting seeds.<br />The experiment was conducted at Sukamulya experimental station of<br />Indonesian Spice and Industrial Crops Research Institute (ISICRI),<br />Pakuwon, Sukabumi from January through November 2010. This<br />experiment was consisted of three factors and three replicates and was<br />arranged in a split-split-plot design. The main plots were two varieties of<br />patchouli, i.e. V1 = Sidikalang and V2 = Lhokseumawe. The sub plots<br />were three plant spacing dimentions, i.e. S1 (1 x 0.5 m), S2 (1 x 0.7 m),<br />and S3 (1 x 1 m). The sub-sub plots were two levels of fertilizer dosage,<br />i.e. F1 (manure; urea, SP-36, and KCl of 30 t; 450, 225, and 450 kg/ha,<br />respectively) and F2 (manure; urea, SP-36, and KCl of 45 t; 300, 150, and<br />450 kg/year, respectively). Variables observed were plant growth (plant<br />height; number of primary, secondary, and tertiary branches), seed<br />productivity and viability, diameter of bottom, medium, and upper of<br />cutting seeds. The results of experiment indicated that Sidikalang variety,<br />treated with 45 tons of manure, 450 kg urea, 225 kg SP-36, and 450 kg<br />KCl per hectare produced the highest number of primary branches<br />compared to other treatments. Plant spacing of 1 x 0.5 m produced the<br />highest number of cutting seeds (73,555 stumps/1,000m 2 ). The averaged<br />diameters of cutting seeds from basal were ≥ 5 mm while those from top<br />were ≥ 4 mm. Viability of the cutting seeds at 0 and 4 days after storage<br />was ≥ 80%. Plant spacing 1 x 0.5 m with dosage of fertilizer 30 ton dung<br />manure, 300 kg urea, 150 kg SP-36, and 300 kg KCl per year is the dosage<br />optimum for producing seed/cutting of patchouli. Combination of fertilizer<br />dosages of 30 tons manure, 300 kg urea, 150 kg SP-36, and 300 kg KCl<br />per year and plant spacing of 1 x 0.5 m produced the highest profit as<br />much as Rp 6,668,500 with B/C value of 2.05.<br />Key words: Pogostemon cablin Benth, plant spacing, fertilizer,<br />production, cutting seed quality</p>

Effects of high plant populations on the growth and yield of winter oilseed rape (Brassica napus)

1999 ◽  
Vol 132 (2) ◽  
pp. 173-180 ◽  
Author(s):  
J. E. LEACH ◽  
H. J. STEVENSON ◽  
A. J. RAINBOW ◽  
L. A. MULLEN
Keyword(s):  
Brassica Napus ◽  
Oilseed Rape ◽  
Plant Density ◽  
High Density ◽  
Growth And Yield ◽  
Winter Oilseed Rape ◽  
Plant Populations ◽  
Rothamsted Experimental Station ◽  
Plant Densities ◽  
Very High

The effects of plant density on the growth and yield of winter oilseed rape (Brassica napus) were examined in a series of five multifactorial experiments at Rothamsted Experimental Station between 1984 and 1989. Plant densities, manipulated by changing the seed rate and row spacing, or because of overwinter losses, ranged from 13·5 to 372 plants/m2. Normalized yields for the multifactorial plots increased with densities up to 50–60 plants/m2. In very high density plots in 1987/88, yield decreased as density increased >150 plants/m2. Plants grown at high density had fewer pod-bearing branches per plant but produced more branches/m2. Branch dry matter (DM) per plant was decreased by 42%, the number of fertile pods per plant and pod DM/plant by 37%. There was no effect of density on the number or DM of pods/m2. Over 74% of the fertile pods were carried on the terminal and uppermost branches of plants grown at high density in 1987/88 compared with only 34% in plants grown at low density in 1988/89. Seed DM/plant decreased with increase in density but seed size (1000-seed weight) increased. There was no effect of density on seed glucosinolate or oil contents.

Influence of size of achenes sown and depth of sowing on growth and yield of dryland oilseed sunflowers (Helianthus annuus) on the Darling Downs

1977 ◽  
Vol 17 (86) ◽  
pp. 489 ◽  
Author(s):  
BJ Radford
Keyword(s):  
Helianthus Annuus ◽  
Plant Density ◽  
Germination Percentage ◽  
Growth And Yield ◽  
Hypocotyl Length ◽  
Plant Populations ◽  
Delayed Emergence ◽  
Development Processes ◽  
Mean Size ◽  
Emergence Percentage

Large achenes of sunflower (Helianthus annuus) exhibited a slightly higher germination percentage and greater mean hypocotyl length than small achenes, resulting in a higher field emergence percentage at sowing depths exceeding 6 cm. Size of achenes sown had no effect on achene yield, provided plant populations from large and small achenes were equal. Plants grown from small achenes produced achenes of higher kernel percentage in both seasons, resulting in higher protein percentage in one season and higher oil percentage in the other. Performance of ungraded achenes was equal to that of graded achenes of the same mean size. Deep sowing reduced emergence percentage considerably, especially when small achenes were sown, but the effect of deep sowing on growth and yield was confounded with effects of reduced plant density (because of reduced emergence) and effects of delayed emergence causing slightly later timing of growth and development processes in relation to environmental factors.

scholarly journals Plant Population Affects Yield and Fruit Size of Pumpkin

HortScience ◽  
1999 ◽  
Vol 34 (6) ◽  
pp. 1076-1078 ◽  
Author(s):  
Stephen Reiners ◽  
Dale I.M. Riggs
Keyword(s):  
Growth Habit ◽  
Plant Competition ◽  
Fruit Size ◽  
Field Studies ◽  
Plant Population ◽  
Lower Yield ◽  
Marketable Yield ◽  
Plant Populations ◽  
Fruit Number ◽  
Row Width

Field studies were conducted in 1996 on two pumpkin (Cucurbita pepo L.) cultivars, `Howden' (vining-type growth habit) and `Wizard' (semi-bush growth habit), at two locations to determine the effect of plant population and row width on marketable yield. Increasing plant populations from 2990 to 8960 plants per hectare resulted in significantly greater fruit number and yield at both locations and for both varieties. Average fruit size declined at the highest populations. Increasing row width from 1.8 to 3.6 m resulted in a slight but significant decrease in number of fruit per hectare with no effect on other yield parameters. At one location, the effect of row width on yield and number of fruit per hectare depended on the population. At low populations, row width did not influence yield or fruit number; at high populations, wide rows produced lower yield and fewer fruit than narrow rows. The results demonstrate that growers may increase pumpkin yield by increasing plant populations but should use narrower row widths and wider in-row spacing. Growers who choose higher populations should ensure that all inputs are optimized to reduce potential plant-to-plant competition and use regionally adapted cultivars.

Yield-density relationships and optimum plant populations in two cultivars of solid-seeded dry bean (Phaseolus vulgaris L.) grown in Saskatchewan

2002 ◽  
Vol 82 (3) ◽  
pp. 521-529 ◽  
Author(s):  
Steven J. Shirtliffe ◽  
Adrian M. Johnston
Keyword(s):  
Seed Weight ◽  
Plant Density ◽  
Maximum Yield ◽  
Plant Population ◽  
Seeding Density ◽  
Seeding Rate ◽  
Higher Plant ◽  
Plant Populations ◽  
Dry Bean ◽  
Density Relationship

There is relatively little agronomic information on solid-seeded production of dry bean in western Canada. Recommended seeding density for dry bean can depend on the growth habit of the plant, the yield–density relationship, percent emergence, seed cost and environment. The objective of this study was to determine the yield–density relationships in two determinate bush type cultivars of dry bean and the optimum plant population under solid-seeded production in Saskatchewan. CDC Camino, a late-season pinto bean and CDC Expresso, a medium-season-length black bean were the cultivars evaluated. In most sites, the yield-density relationship of the cultivars was asymptotic and an optimum plant density for maximum yield could not be determined. Camino generally required a lower plant population to reach a given yield than Expresso. Increasing plant population did not affect 1000-seed weight. Higher seeding rate did result in a greater number of seeds produced m-2, with Expresso having a greater increase in seed produced m-2 compared with Camino. Expresso was required to be at higher plant densities than Camino to maximize economic returns. This reflects the differences between cultivars in yield-density relationship and seed cost, as Camino has a heavier 1000-seed weight than Expresso. Saskatchewan bean growers wishing to maximize profit should target plant populations for Expresso and Camino of approximately 50 and 25 plants m-2, respectively. Key words: Saskatchewan, yield components, non-linear regression, seeding rate, narrow rows, solid-seeded

scholarly journals Simulated mesotrione drift followed by glyphosate, imazethapyr, bentazon or glyphosate plus chlorimuron in soybean

2009 ◽  
Vol 89 (2) ◽  
pp. 265-272
Author(s):  
L. R. Brown ◽  
D. E. Robinson ◽  
K. Chandler ◽  
C. J. Swanton ◽  
R. E. Nurse ◽  
...  
Keyword(s):  
Glycine Max ◽  
Key Words ◽  
Plant Height ◽  
Seed Yield ◽  
Plant Density ◽  
Dry Weight ◽  
Shoot Dry Weight ◽  
Glycine Max L ◽  
Herbicide Drift

There have been anecdotal accounts of increased crop sensitivity due to herbicide drift followed by an in-crop herbicide. An experiment was conducted from 2005 to 2007 at Elora, Ridgetown, and Woodstock, Ontario, to determine the effects of simulated mesotrione drift followed by in-crop applications of glyphosate, imazethapyr, bentazon and glyphosate plus chlorimuron on glyphosate-resistant soybean [Glycine max (L.) Merr.] visual injury, plant height, plant density, shoot dry weight, and seed yield. As the rate of simulated mesotrione drift increased, there was an increase in soybean injury and a decrease in shoot dry weight, height, and yield. Simulated mesotrione drift followed by bentazon resulted in synergistic responses in injury shortly after application in some environments. This increase in injury was transient, with no synergistic responses in density, shoot dry weight, and yield. In contrast, antagonistic responses were observed when glyphosate, imazethapyr, or glyphosate plus chlorimuron were applied after simulated mesotrione drift in some environments. Further research is required to develop a better understanding of the interactions of drift followed by the application of an in-crop herbicide. Key words: Bentazon, chlorimuron, glyphosate, imazethapyr, mesotrione, synergism

Interaction of nutrient supply and plant density in relation to maximal yield of the swede crop

1968 ◽  
Vol 70 (3) ◽  
pp. 369-373 ◽  
Author(s):  
R. W. Lang ◽  
J. C. Holmes
Keyword(s):  
Plant Density ◽  
Total Yield ◽  
Nutrient Supply ◽  
Matter Content ◽  
Human Consumption ◽  
Dry Matter Content ◽  
Small Populations ◽  
Plant Populations ◽  
Maximal Yield ◽  
Large Populations

SUMMARYThe effects of changing plant density and nutrient supply on the yield of swedes were measured in nine experiments over 3 years. With small populations, a large nutrient supply was required to reach the maximal yield of roots, but with large plant populations the same nutrient rate depressed yield. This interaction is illustrated by a response surface, and reasons for it are discussed. The interaction is of limited importance in practice because it was small over the range of population and nutrient supply commonly used. Even with small populations, the compensation achieved by applying more fertilizer was uneconomic. On crops with large populations, such as swedes for human consumption, however, the normal recommended rate of fertilizer should not be exceeded because of loss of yield as well as increased cost. More fertilizer and greater plant density were needed to give maximal total yield (roots + tops) than of roots alone. Effects of nutrient supply and plant population on plant establishment and dry-matter content of the swedes are discussed.

Density Estimates of Mysis relicta in Lake Michigan

1979 ◽  
Vol 36 (6) ◽  
pp. 694-698 ◽  
Author(s):  
Nevin E. Grossnickle ◽  
Mark D. Morgan
Keyword(s):  
Key Words ◽  
Lake Michigan ◽  
Density Estimates ◽  
Mysis Relicta ◽  
Deep Station ◽  
Late Instar ◽  
Order Of Magnitude

Density estimates of Mysis relicta based on night vertical net tows at stations of 30–50 m in Lake Michigan were about an order of magnitude larger than previous estimates based on sled tows. Significantly greater density estimates were obtained in night vertical net tows than those collected before sunset at these shallow stations. However, density estimates based on sled tows during daylight were not significantly different from those based on night vertical net tows at a 115-m station in Lake Michigan. At this deep station, a substantially larger percentage of late instar mysids was collected in sled tows than in night vertical net tows. Key words: Mysis relicta, Lake Michigan, density estimates, vertical net tows, epibenthic sled tows

Morphological, ecological and genetic variability of Lavandula luisieri (Rozeira) Rivas-Martínez in central eastern Portugal

2010 ◽  
Vol 8 (1) ◽  
pp. 82-90 ◽  
Author(s):  
Fernanda Delgado ◽  
Sílvia Ribeiro ◽  
Álvaro Alves ◽  
Eliseu Bettencourt ◽  
Sónia Dias
Keyword(s):  
Genetic Similarity ◽  
Plant Density ◽  
Plant Traits ◽  
Morphological Variability ◽  
Cultivated Plants ◽  
Interior Region ◽  
Plant Populations ◽  
Phenotypic Data ◽  
Genetic Characteristics ◽  
Central Eastern

The morphological characterisation and data analysis of germplasm accessions of wild Portuguese Lavandula luisieri (Rozeira) Rivas-Martínez from the southern Beira Interior region of central eastern Portugal are described. The study, based on seeds and cultivated plants, was conducted in 2005, 2006 and 2008 among populations selected from four sites (I, II, III and IV). Quantitative and qualitative phenotypic data relating to a set of 35 morphological traits were analysed using canonical discriminant analysis. Genetic similarity among accessions was assessed using amplified fragment length polymorphism molecular markers. The traits contributing most to the variability among studied populations were related to plant density, leaf colour, seed weight and various spike and flower characteristics. Plant populations from each of the four test sites were statistically distinct, exhibiting unique characteristics when compared with one another; however, populations from Sites II, III and IV showed greater genetic similarity and differed substantially from the population of Site I. Altitude and temperature were found to be the most significant environmental variables influencing plant traits, yet the morphological variability of L. luisieri was also influenced by soil pH levels, suggesting that the expressed variability is not only a result of genetic characteristics but also of existing ecological conditions.

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