Effect on Single Plant, Main Spike Yield and Some Yield Components in Bread Wheats of
Different Plant Populations in Ecological Conditions of Central Anatolia
Abstract
This study was conducted to determine effect on single plant and single plant per main spike yield and some yield components in Ahmetaga and Bezostaja-1 bread wheats having more and few tillers, respectively as a function of tillering of ecological conditions and different plant populations in Konya ecological conditions during 2007-2008 and 2009-2010 growing seasons. Experimental design was “in randomized complete block design as three factors” with three replications. In this study, wheat seeds were planted in 7 intra row spaces “normal, 2.5, 5.0, 7.5, 10.0, 12.5 and 15 .0 cm”. It was determined that there were statistically significant differences in effect of ecological conditions (years), intra row spaces, varieties and their interactions on plant height, spike length, spikelet number, grain number and grain yield measured in single plant per main spike, fertile tiller number, total tiller (fertile + infertile ) number and biological yield in per single plant. In the study, other studied all traits out of plant height highly increased as plant population was decreased. Maximum and minimum data were obtained from 15.0 cm and normal of intra row spaces, respectively. Intra row spacing of 15.0 cm was lower 11.8% for plant height and higher 20.2% for spike length, 18.4% for spikelet number, 58.3% for grain number, 62.5% for grain yield, 694.4% for fertile tiller number, 647.0% for total tiller number and 991.9% for biological yield. Ahmetaga variety for all traits out of plant height was higher than Bezostaja-1 variety. Ahmetaga variety was greater 31.2% for fertile tiller number per single plant and 19.3% for grain yield in single plant per main spike. Ecological conditions affected highly studied all traits.
Keywords: Bread wheat, intra row space, plant population, ecological conditions
Orta Anadolu Ekolojik Şartlarinda Farkli Bitki Popülasyonlarinin Ekmeklik
Buğdaylarda Tek Bitki, Ana Başak Verimi Ve Bazi Verim Bileşenleri Üzerine Etkisi
Hayati AKMAN1 Ali TOPAL21Selçuk University, Sarayönü Vocational School of Higher Education, 42430, Konya 2Selçuk University, Faculty of Agriculture, Department of Field Crops, 42075, Konya
*Corresponding author: E-mail: hayatiakman@selcuk.edu.tr
Özet
Bu çalışma 2007-08 ve 2009-10 yıllarında Konya ekolojik şartlarının sırasıyla az ve çok kardeşlenen Bezostaja-1 ve Ahmetağa ekmeklik buğdaylarda tek bitki ve ana başaktaki tek bitki verim ve bazı verim bileşenlerini üzerine etkisini belirlemek amacıyla yürütülmüştür. Araştırma tesadüfi blokları deneme desenine göre üç tekerrürlü olarak dizayn edilmiştir. Buğday tohumları normal (çiftçi uygulaması), 2.5, 5.0, 7.5, 10.0, 12.5 ve 15.0 cm sıra üzeri olmak üzere yedi farklı sıra üzeri mesafesinde ekilmiştir. Ana başaktaki tek bitkide ölçülen bitki boyu, başak uzunluğu, başakçık sayısı, tane sayısı ve tane verimi ve tek bitkide ise fertil kardeş sayısı, toplam kardeş sayısı ve biyolojik değerler üzerine ekolojik şartların, sıra üzeri mesafesinin, çeşitlerin ve kendi aralarındaki interasyonların etkisi istatistiki olarak önemli bulunmuştur. Araştırmada, bitki popülasyonu azaldıkça bitki boyu dışındaki tüm parametreler artış göstermiştir. Maksimum ve minimum değerler sırasıyla 15.0 cm sıra üzeri mesafesinde ve normal ekimde elde edilmiştir. 15.0 cm sıra üzerine ekimde normal sıra üzerine ekime göre bitki boyu %11.8 daha kısa, başak uzunluğu %20.2, başakçık sayısı %18.4, tane sayısı %58.3, tane verimi %62.5, fertil kardeş sayısı %694.4, toplam kardeş sayısı %647.0 ve biyolojik değer %991.9 daha yüksek bulunmuştur. Ahmetağa çeşidi bitki boyu dışındaki incelenen tüm özellikler bakımından Bezostaja-1 çeşidinden daha yüksek bulunmuştur. Ahmetağa çeşidi, tek bitkideki fertil kardeş sayısı bakımından %31.2 ve ana başaktaki tek bitkideki tane verimi bakımından ise %19.3 daha yüksek bulunmuştur. Ekolojik şartların incelenen tüm özellikleri önemli derecede etkilemiştir.
Anahtar kelimeler: Ekmeklik buğday, sıra üzeri mesafesi, bitki popülasyon Biyoloji Bilimleri Araştırma Dergisi 5(2): 25-30, 2012 ISSN: 1308-3961, E-ISSN: 1308-0261, www.nobel.gen.tr
INTRODUCTION
That wheat is one of the most important staple cereal crops is grown on an area of 8.03 million hectares with total production of 20.6 million tons and an average yield of 2566 kg ha-1 in Turkey (Anonymous, 2011). Wheat production may be increased effectively when crop production practices, variety traits and tolerant varieties to environmental conditions are considered in terms of how to affect crop production.
Plant population is one of major limited factors affecting wheat production. Seed density used for wheat is suggested between 450-550 viable seed per square meter, which is does not take into account genotype differences, especially concerning tiller production and survival (Valerio et al., 2009). Plant population per square meter decreases due to emergence problems caused by biotic and abiotic factors. However, varieties with more tillers can balance yield through increasing plant population. Tillering function as variety characteristic can be great of getting maximum yield and avoiding yield decrease. Tillering is important a trait affecting grain yield, depending on variety genetics, environmental factors and production practices (Genctan and Balkan, 2006). Not only is surviving tillers, fertile tillers also have great importance of getting potential yield. Tonkin (2004) reported that grain number, size and weight per spike was found greater main stem spike, gradually reduced those of other tillers in single plant. She also stated that tillers inclined to have longer crop ripening period than main stem, therefore it was possible that high plant population decreasing tiller numbers provided to have shorter ripening period and more uniform seed.
The present study was conducted to investigate response on single plant yield and some yield components in bread wheats
tillering few and more of environmental conditions and different plant populations.
MATERIAL AND METHOD
This study was conducted to determine response on single plant yield and yield components in bread wheats tillering few and more of environmental conditions and different plant populations in Konya during 2007-08 and 2009-10 Experimental design was “in randomized complete block design” with three replications. Ahmetaga and Bezostaja-1 varieties having more and few tillers respectively were used to material. Fertilizers were applied to 111 kg ha-1 diammonium phosphate (18 % nitrogen and 46 % phosphate) in planting, 80 kg ha-1 ammonium nitrate (33% nitrogen) in tillering and heading stages as two parts. Plots were watered twice by sprinkler irrigation system after planting and in heading stage.
Plots were dimension of 1.5 × 1 meter forming four rows, which were planted 20 cm row space with seven different intra row spaces that were normal, 2.5, 5, 7.5, 10.0, 12.5 and 15 cm. The seeding rate of normal application was calculated to be 500 seeds m-2 for both varieties. In ten plant selected per plot in harvest, it was measured plant height, spike length, spikelet number per spike, grain number per spike, grain weight per spike in main stem of single plant and fertile tiller number, total tiller number, biological yield in single plant. Those physical and chemical properties of experiment soil were analyzed before the planting was given in Table 2. Statistical analysis was performed with MSTAT-C statistic program and significant differences between means were tested by analysis of variance, followed pairwise comparisons by LSD test.
*Data was taken from Konya Meteoroloji Station
Table 1. Average temperature and precipitation data including 1972-2007, 2007-2008 and 2009-2010 in Konya
Months 1972-2007 2007-2008 2009-2010 Temperature (oC) Precipitation (mm) Temperature (oC) Precipitation (mm) Temperature (oC) Precipita tion (mm) September 18.7 11.8 20.0 4.1 18.1 21.0 October 12.6 32.4 14.0 25.5 15.5 12.7 November 5.9 36.8 7.0 68.0 6.6 56.7 December 1.5 41.6 1.2 53.8 4.8 74.6 January -0.2 34.9 -3.5 16.5 3.0 44.2 February 1.1 24.5 -2.7 21.2 5.8 28.1 March 5.6 25.9 9.8 38.1 8.6 12.6 April 11.0 39.3 14.1 20.5 11.1 41.4 May 15.8 42.2 15.7 23.4 17.5 18.8 June 20.4 20.8 22.0 7.5 20.9 39.8 July 23.6 7.6 24.6 5.5 26.2 2.4 August 23.1 5.1 26.0 0.0 27.6 0.7 Total - 322.7 - 284.1 - 353.0 Average 11.6 - 12.4 - 13.8 353.0
Table 2. Physical and chemical properties of the experiment soil in 0-20 and 20-40 cm
Sand Loam Clay PH EC CaCO3 Organic
matter Inorganic Nitrogen P % % % µS cm- % % mg kg- mg kg- mg kg -0-20 cm 34 24 38 8.00 182 19.04 1.96 44.80 6.57 20-40 cm 54 14 32 8.02 190 19.44 1.11 42.28 8.13 K Ca Mg Na B Cu Fe Zn Mn mg kg- mg kg- mg kg- mg kg- mg kg- mg kg- mg kg- mg kg- mg kg -0-20 cm 692 3875 183 45 1.25 0.36 1.80 0.34 3.8 20-40 cm 683 4008 185 41 1.35 0.36 1.06 0.28 3.2
Table 3. Response of main spike yield and some yield components of environmental conditions and different plant populations in bread wheats Plant height per main spike
2007-2008 2009-2010
Irs (cm) A.aga Bezos. Mean A.aga Bezos. Mean V1 × Irs V2× Irs Irs
1 69.9 74.5 72.2 97.1 110.7 103.9 83.5 92.6 88.0a 2.5 73.6 76.7 75.2 96.9 103.1 100.0 85.3 89.9 87.6a 5 66.9 74.4 70.7 103.0 100.0 101.5 85.0 87.2 86.1ab 7.5 64.6 71.4 68.0 93.5 105.8 99.7 79.0 88.6 83.8abc 10 67.8 72.6 70.2 97.3 99.4 98.3 82.6 86.0 84.3abc 12.5 62.5 71.6 67.1 91.1 95.7 93.4 76.8 83.6 80.2bc 15 59.2 68.5 63.9 92.3 94.7 93.5 75.7 81.6 78.7c
Mean 66.4 72.8 69.6B 95.9 101.3 98.6A 81.1b 87.1a
*Year, variety and irs P ≤0.01; A.aga:Ahmetağa variety and V1; Bezos.: Bezostaja-1 variety or V2;Irs: intra row spaces Spike length per main spike
2007-2008 2009-2010
Irs (cm) A.aga Bezos. Mean A.aga Bezos. Mean V1 × Irs V2× Irs Irs
1 7.7 6.9 7.3 9.9 9.1 9.5 8.8 8.0 8.4b 2.5 8.1 7.8 8.0 10.2 8.9 9.6 9.2 8.4 8.8b 5 8.7 9.0 8.9 11.5 10.1 10.8 10.1 9.5 9.8a 7.5 8.9 8.7 8.8 10.9 10.5 10.7 9.9 9.6 9.8a 10 8.9 9.2 9.1 10.9 10.8 10.9 9.9 10.0 10.0a 12.5 9.7 9.4 9.5 11.1 10.3 10.7 10.4 9.9 10.1a 15 8.9 9.0 9.0 11.5 11.1 11.3 10.2 10.1 10.1a
Mean 8.7c 8.6c 8.6B 10.9b 10.1a 10.5A 9.8a 9.4b
*Year, variety and irs P ≤0.01; year × variety interaction P ≤0.05
Spikelet number per main spike
2007-2008 2009-2010
Irs (cm) A.aga Bezos. Mean A.aga Bezos. Mean V1 × Irs V2× Irs Irs
1 13.9 15.1 14.5 17.1 17.1 17.1 15.5g 16.1 g 15.8b 2.5 15.4 15.4 15.4 19.5 16.9 18.2 17.5 f 16.1 g 16.8b 5 18.2 17.3 17.8 20.6 18.3 19.5 19.4 ab 17.8def 18.6a 7.5 18.1 17.0 17.5 20.2 18.3 19.2 19.1abc 17.6ef 18.4a 10 17.8 17.9 17.9 20.6 18.4 19.5 19.2abc 18.2c-f 18.7a 12.5 19.0 17.5 18.2 20.5 18.2 19.4 19.8a 17.8def 18.8a 15 17.0 17.8 17.4 20.8 19.4 20.1 18.9 a-d 18.6b-e 18.7a
Mean 17.1c 16.9c 17.0B 19.9a 18.1b 19.0A 18.5a 17.5b
*Year, variety, irs and year × variety interaction P ≤0.01; variety × irs P ≤0.05 Grain number per main spike
2007-2008 2009-2010
Irs (cm) A.aga Bezos. Mean A.aga Bezos. Mean V1 × Irs V2× Irs Irs
1 31.0 25.6 28.3 42.7 26.4 34.6 36.9 26.0 31.4c 2.5 36.0 31.4 33.7 49.2 22.4 35.8 42.6 26.9 34.8c 5 47.0 43.9 45.5 49.3 30.5 39.9 48.2 37.2 42.7b 7.5 43.2 41.7 42.5 54.1 31.3 42.7 48.7 36.5 42.6b 10 46.2 39.2 42.7 58.0 37.3 47.7 52.1 38.3 45.2ab 12.5 53.0 44.9 49.0 57.5 37.0 47.3 55.3 41.0 48.1ab 15 49.1 46.1 47.6 59.8 43.8 51.8 54.4 45.0 49.7a
Mean 43.6b 39.0b 41.3 53.0a 32.7c 42.8 48.3a 35.8b
RESULTS AND DISCUSSION
Plant height per main spike (cm)Plant height varied to be based on variety genetics and production practices. Nitrogen fertilizer application and plant density have great of importance to plant height.
It is found that there were statistically significant differences in years, varieties and intra row spaces on plant height per main stem (P ≤0.01) (Table 3). The higher and minimum plant heights were obtained 88 cm and 78.7 cm from 15 cm and normal of spacing, respectively. This study agreed with work by Soomro et al. (2009) who reported that wheat with higher seed densities produced greater plant height. Plant height in higher plant density is greater that is why plant competition between plants increases for reaching to light.
Average plant height of Bezostaja-1 variety with 87.1 cm was higher than Ahmetaga variety with 81.1 cm. Plant height in 2007-08 and 2009-10 years varied from 69.6 to 98.6 cm, respectively. In 2009-10, plant height increased greatly as rainfall was high.
Spike length per main spike (cm)
Data presented Table 3 indicated that years, varieties, intra row spaces (P ≤0.01) and year × variety interaction (P ≤0.05) had highly significant effect on spike length per main stem. Maximum spike length was 10.1 in 12.5 and 15.0 cm of intra row spaces whereas minimum spike length was 8.4 cm in normal intra row spacing. Spike length decreased as plant population increased. Similar results were recorded by
Dinc (2010). 1st year the spike length was 8.6 cm while 2nd year was 10.5 cm. Spike length of Ahmetaga variety was greater than Bezostaja-1.
Spikelet number per main spike (no)
Table 3 showed that years, varieties, irs, year × variety interaction (P ≤0.01) and variety × irs (P ≤0.05) interaction had significant effect on spikelet number per main spike. Maximum spikelet number was found in 5, 7.5, 10, 12.5 and 15 cm of intra row spaces, minimum was found in normal of that. Spikelet numbers the minimum and maximum was obtained 17.0 and 19.0 in first and second year, respectively. Spikelet number of Ahmetaga variety was greater than Bezostaja-1, 18.5 and 17.5, respectively. Similar finding was reported by Dogan et al. (1997). They noted that spikelet number reduced as plant population increased.
Grain number per main spike (no.)
Data given Table 3 indicated that varieties, irs and year × irs interaction (P ≤0.01) had highly significant effect on grain number per main spike. Minimum and maximum grain number was found 31.4 and 49.7 in normal and 15 cm of intra row spaces, respectively. This study was agreement with work by Khan et al. (2000) and Habibullah et al. (2007) reported that grain number increased as plant population decreased. Grain number the Ahmetaga variety was higher both years and greater 34.9 % than Bezostaja-1 variety.
Grain yield per main spike (g)
It was found that there were statistically significant difference in years, varieties, intra row spaces and year × variety interaction on grain yield per main spike (P ≤0.01) (Table 4). Minimum and maximum grain yield was obtained 1.20 g and 1.95 g from normal and 15 cm of intra row spaces, respectively. Hussain et al. (2010) stated that grain yield
increased as seed rate was increased from 50 kg to 150 kg ha -1
.Furthermore Khalıq et al. (1999) noted that yield increased from 3.78 to 4.47 g as seed rate was increased from 100-200 kg ha-1. They revealed that yield increased as seed rate was increased, whereas this study was not only carried out in only main stem, seed rate or plant density had highly low, so it was found grain yield per main stem decreased as seed rate increased. Ahmetaga variety having more tillers the grain yield per main spike had 19.3 % greater than Bezostaja-1. Grain yield per main spike was 1.51 and 1.78 g in 2007-08 and 2009-10, respectively. Data given Table 4 showed that environmental conditions affected significantly to grain yield per main spike up to 17.9 % increase in 2nd year.
Fertile and total (fertile + infertile) tiller number per single plant (no.)
Tillering occurs by emerging many stems from a germinated seed. It could be advantage to balance to yield where low in plant density result in the area grown wheat. Tillering varies to depend on variety genetics, environmental factors and production practices such as fertilizer, irrigation, plant density, rainfall, drought stress.
Years, varieties, intra row spaces and year × intra row spaces interaction had highly significant effect on fertile tiller number per single plant (P ≤0.01). Minimum fertile and total tiller number was obtained from normal of intra row spaces, whereas maximum of that was obtained from 15 cm of those that was higher up to 694.4 and 647.0% increase in fertile and total tiller number, respectively. Claudhry and Hussain (2001) reported that fertile tiller number increased as plant density resulting from increasing seed rate increased. However, data given Table 4 indicated that fertile and total tiller number per single plant increased as plant density decreased. Researchers take consider into while studying with wheat stages and wheat varieties that had different tiller number.
Because, for example, Zadoks scale points that 29th growth
stage where main shoot and at least 9 tillers includes, however this stage was found in 7.5 cm of Ahmetaga and 15 cm of Bezostaja-1 in intra row spaces in this study. As researchers can’t observe some tillering stages in their studies when higher plant density, different variety and environmental conditions are worked with, it should be suggested to be used main growth stages such as 20-29th as tillering stage by them.
Infertile tiller number in 15 cm of intra row spaces was higher up to 242.1 % increase than normal of those. Infertile tiller number decreased highly as plant density increased.
Ahmetaga variety had more fertile tiller number up to 32.2 % and total tiller number up to 28.9 % than Bezostaja-1 variety. 2nd year had highly fertile and total tiller because environmental conditions increased tiller number per single plant.
Biological yield (g)
It was evidence from Table 4 showed that years, varieties, intra row spaces, year × irs and year × variety had highly significant on biological yield per single plant (P ≤0.01). Minimum and maximum biological yield were obtained 4.32 and 47.17 g in normal and 15 cm of intra row spaces, respectively. Khan et al. (2000) indicated that biological yield increased as seed rate increased. But, this study revealed that single plant weight was increased by increase in tiller number per single plant. In 2009-10, biological yield was greater due to more rainfall. Biological yield of Ahmetaga variety was higher that was why all parameters apart from plant height were greater than Bezostaja-1.
Table 4. Response of single plant and main spike yield and some yield components of environmental conditions and different plant populations in bread wheats.
Grain yield per main spike
2007-2008 2009-2010
Irs (cm)
A.aga Bezos. Mean A.aga Bezos. Mean V1×Irs V2×Irs Irs
1 1.17 1.03 1.10 1.37 1.23 1.30 1.27 1.13 1.20d 2.5 1.44 1.20 1.32 1.97 0.93 1.45 1.70 1.07 1.38cd 5 1.59 1.71 1.65 1.85 1.37 1.61 1.72 1.54 1.63bc 7.5 1.37 1.62 1.49 2.23 1.51 1.87 1.80 1.57 1.68abc 10 1.68 1.56 1.62 2.19 1.53 1.86 1.94 1.54 1.74ab 12.5 1.79 1.76 1.78 2.36 1.53 2.08 2.08 1.78 1.93ab 15 1.57 1.69 1.63 2.44 1.8 2.27 2.01 1.89 1.95a
Mean 1.52b 1.51b 1.51B 2.06a 1.50b 1.78A 1.79a 1.50b
*Year, variety, irs and year × variety interaction P ≤0.01
Fertile tiller number per single plant
2007-2008 2009-2010
Irs (cm)
A.aga Bezos. Mean A.aga Bezos. Mean V1×Irs V2×Irs Irs
1 1.30 1.10 1.20f 2.03 2.04 2.04ef 1.67
1.57
1.62e
2.5 2.53 2.71 2.62ef 5.18 7.54 6.36de 3.86 5.13 4.49de
5 3.33 2.67 3.00ef 11.43 10.17 10.80cd 7.38 6.42 6.90cd
7.5 3.50 2.83 3.17ef 15.36 10.42 12.89bc 9.43 6.63 8.03bc
10 4.20 2.94 3.57ef 14.92 13.03 13.97bc 9.56 7.98 8.77bc
12.5 4.50 3.63 4.07ef 20.06 13.64 16.85b 12.28 8.64 10.46ab
15 4.10 2.90 3.50ef 28.17 16.32 22.24a 16.13 9.61 12.87a
Mean 3.35 2.68 3.02B 13.88 10.45 12.07A 8.62a 6.57b
*Year, variety, irs and year × irs interaction P ≤0.01
Total tiller number per single plant
2007-2008 2009-2010
Irs (cm)
A.aga Bezos. Mean A.aga Bezos. Mean V1×Irs V2×Irs Irs
1 1.37 1.10 1.23f 2.58 2.21 2.39ef 1.97 1.65 1.81e
2.5 2.83 2.84 2.84ef 5.49 8.29 6.89de 4.16 5.57 4.86de
5 3.80 3.10 3.45ef 12.12 10.50 11.31cd 7.96 6.80 7.38cd
7.5 4.03 3.60 3.82ef 16.09 10.93 13.51bc 10.06 7.27 8.67bc
10 4.77 3.37 4.07ef 15.83 13.58 14.71bc 10.30 8.48 9.39bc
12.5 4.93 4.43 4.68ef 20.91 14.72 17.82b 12.92 9.58 11.25ab
15 4.90 3.40 4.15ef 28.50 17.29 22.90a 16.70 10.35 13.52a
Mean 3.81 3.12 3.46B 14.50 11.08 12.79A 9.15a 7.10b
*Year, variety, irs and year × irs interaction P ≤0.01
Biological yield per single plant
2007-2008 2009-2010
Irs (cm)
A.aga Bezos. Mean A.aga Bezos. Mean V1×Irs V2×Irs Irs
1 1.62 2.68 2.15e 5.43 7.52 6.48e 3.53 5.10 4.32e
2.5 6.18 7.61 6.90e 18.80 18.77 18.78de 12.49 13.19 12.84de
5 7.80 10.22 9.01e 42.50 24.10 33.30cd 25.15 17.16 21.16cd
7.5 9.86 9.33 9.59e 54.67 33.40 44.03c 32.26 21.36 26.81bc
10 12.48 9.92 11.20e 51.33 42.37 46.85bc 31.91 26.14 29.03bc
12.5 10.98 11.11 11.05e 73.50 48.37 60.93b 42.24 29.74 35.99ab
15 10.63 10.51 10.57e 98.03 69.50 83.77a 54.33 40.01 47.17a
Mean 8.51c 8.77c 8.64B 49.18a 34.86b 42.02A 28.85a 21.82b
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