Effect of Planting Times Growth and Yield of White Lupen (Lupinus albus L.)

This experiment was carried out in the field crops research area of Harran University in Eyyübiye Campus of Þanlýurfa, Turkey in 2017 as winter crop. The lupine (white lupine) seeds (Lupinus albus L.) used in the study, which was the population obtained from the growers who grow white lupine in and around Antalya.     
        
For the analysis of soil, samples were taken from 0-30 cm depth in the experimental field, average contents of organic matter, CaCO₃, plant available phosphorus and potassium were 1.23%, 5.40%, 3.60 kg da^-1 and 9.3 kg da^-1 (da = meters), respectively. Overall, soils were high in lime and potassium contents, whereas poor in organic matter and phosphorus contents. The soil of the experimental area is clay in texture and pH slightly alkaline.
        
During experimental period, the lowest average temperature was 5.5°C in January and the highest average temperature was 33.0°C in June. According to the long terms average temperature values, the lowest average temperature was 5.7°C in January and the highest average temperature was 28.2°C in June. While the amount of rainfall was 17.1 mm in October, 4.5 times higher rainfall was observed in November and December. The plants did not get enough rainfall in spring season. In April and May, which were the flowering and pod set times of crops, rainfall amounts were 49.6 and 25.6 mm, respectively.
        
The research trial was conducted in the growing season of 2017 on the field crops research area of Eyyubiye campus that represents the ecological conditions of the Harran plain in the province of Þanlýurfa. The experiment was carried out in a randomized complete block design with 4 replications. The crop was planted as per the different sowing times of October 15, November 15, November 30 and December 15, respectively. Accordingly, each block was consisted of 4 plots with 6 rows. Plot size was 70´20 cm, row length was 5 m and each parcel area was set as 5 × 0.7 × 6 = 21.0 m². Calculating 15 kg seed per decares; 315 g of each parcel, 53.0 g of white lupine (Lupinus albus L.) seeds were used in each row. In the experiment, the parcels were fertilized with 4 kg pure (available) N and 8 kg pure  (available) P₂O₅ decares (Okuyucu et al., 2004). In the harvest operations, the first and last rows of each parcel together with the first and last 50 cm portions of each parcel were discarded as border effect and the remaining area (4 ´ 1.4 ´ 2 = 11.2 m²) was determined as harvesting area. The observations and measurements related to the characters to be evaluated were made in this area. Half of the trial plot (2 rows) was harvested for observations of hay yield and the other half (2 rows) was harvested for observations about seed yield. Harvesting of white lupines were performed at the end of flowering and when the lower beans begin to ripen for green grass; while for seed, it was performed when beans get yellowish and ripen.
        
The plant height and the number of branches per plant were determined by taking average measurements of 10 randomly selected plants from each plot between soil surfaces and last bud in cm. The weights of each plot were determined by weighing their green weights in the field conditions. 500 g of green grass samples harvested from each parcel were taken and dried in a oven at 70°C for 48 hours and hay yields of each parcel were determined by weighting dried weed samples. After harvesting plants from each parcel, seeds were dried and 100 seed weight and seed yields were calculated. The yield values determined per plot were converted to yield per decares. Plant samples taken from dry grass were milled in a mill with a sieve diameter of 1 mm and used for analysis. The Kjeldahl method was used to determine the nitrogen (N) content of the samples. The crude protein ratio was calculated by multiplying the nitrogen ratio by 6.25 (AOAC, 1990).
        
The data obtained at the end of the study were evaluated using JMP statistical package program and LSD test was used to determine the significance level of the differences between the means.

Plant characteristics, green grass and hay yields and quality characteristics of lupen sown at different sowing dates under the ecological conditions of the Harran plain of Þanlýurfa province in the winter season of 2017, are presented in Table 1 and 2.
 

 

 
Plant height (cm)
 
There is no significant difference in average plant height due to different sowing times, the highest plant height of 30.46 cm was found in 30 October sowing crop (Table 1). Various studies conducted on different lupen genotypes in different ecologies reported the  plant height of 38.70-91.70 cm (Okuyucu et al., 2004; Georgieva et al., 2018; Kosev and Vasileva, 2019). The lower height recorded in this study could be due to the low rainfall during the vegetation period  and planting in the autumn.
 
Number of branches (per plant^-1)
 
The different sowing times did not influence significantly on the number of branches per plant. However, the maximum number of branches per plant of 2.79 was recorded in the crop December 15 sowing (Table 1).
        
There are different studies on white lupen, which is a one-year legume forage plant from the same family in different ecologies and different genotypes. In Diyarbakýr, Seydoþoðluet_al(2015) in his study reported main stems of the bitter vetch as 1.87- 2.53 pieces plant^-1. The variation in the findings of this study and findings of other studies could be to the conditions of upbringing.
 
Green grass yield (kg da^-1)
 
Green grass yield of lupine was found to be statistically significant with the sowing at different times. It can be observed that average green grass yield varied between 611.21-1178.57 kg da^-1, the highest was observed in October 30 sowing and the lowest was found in October 15 sowing (Table 1).
        
The different studies were conducted with different lupine genotypes in different ecologies and reported different amount of green grass yield vary from 3640-5420 kg da^-1  in Brazil (Badina, 1972), 3000-6000 kg da^-1 in Russia (Khrenikov, 1972)  and 2193-8448 kg da^-1 in Izmir (Okuyucu et al., 2004). The lower yield obtained in the this study than the previous studies might be due to the different genotypes used, soil characteristics and precipitation received during the crop season.
 
Dry hay yield (kg da^-1)
 
The dry matter yields were varied statistically significant under different sowing times (Table 1). It was seen that average hay yield varied between 172.65-358.77 kg da^-1. The highest hay yield of 358.77 and 323.86 kg da^-1) were recorded in 30 November and 30 October parcels.
        
Okuyucu et al., (2004) conducted study in Ýzmir reported that the dry matter yield of lupens was of 288-1057 kg da^-1. There are  different studies on white lupen, which is a one-year legume forage plant from the same family. Seydoþoðluet_al(2015) reported that hay yield of pea genotypes was obtained as 330.67-767.38 kg da^-1. It is thought that genotype and environment are the reasons of similarities or differences between the results of this study and other studies.
 
Seed yield (kg da^-1)
 
As shown in Table 3, the highest seed yields were obtained in 30 November, 15 November and 15 December sowing of 212.57, 209.90 and 208.92 kg da^-1, respectively, while the lowest seed yield 185.39 kg da^-1 was recorded in 30 October sowing.
        
The study conducted  by Okuyucu et al., (2004) reported the seed yield of 184-280 kg da^-1 of lupens in Ýzmir. There are also different studies conducted for seed yield of grass pea, a one-year legume forage plant in the same family of white lupen. Seydoþoðluet_al(2015) found the seed yield of grass pea genotypes ranging from 181.00 to 269.83 kg da^-1 in Diyarbakýr. Seed yield is a quantitative character that is highly affected by environmental conditions. High seed yields in southeastern Anatolia conditions may be due to ecological and genotypic differences in experiments.
 
100-seed weight (g)
 
100-seed weight (g) of white lupen varied between 9.43-13.23 g but highest was observed in October 30 sowing (Table 2). There were three different groups among different sowing times for 100 seed weight of white lupen.
        
There were different studies conducted on white lupine, which was one year of legume forage plants and with others in the same family. According to Georgieva et al., (2018), the weight of 1000-seeds of white lupen in Pleven was 174.50-322.18 g. Seydoþoðluet_al(2015) recorded the weight of 1000-seed grass pea was 99.88-141.71 g in Diyarbakir.
        
The reason for the similarity or inconsistency between the results of this study and the findings of other researchers was due to the diffrent sowing times and the locations of studies.
 
The crude protein in dry grass
 
Although, there was no differences in average values of crude protein content of hay with different sowings, numerically, the highest crude protein in hay  was observed of 19.53% in the November 15 planting time. The average crude protein of hay recorded in different sowings was 18.00% (Table 2).
        
The studies conducted on lupen in different ecologies were determined the crude protein content in hay. In France, Gatel (1994) measured the proportion of protein in the vegetable parts of lupine as 17.00-22.27%. Protein content in lupines in Konya was found as 28.0-47.6% (Hakkýet_al2007). The protein differences between genotypes may be due to leaf stem ratio and growth stage. In other words, crude protein of genotypes, which have high leaf ratio, also have higher crude protein (Yucel et al., 2012).
        
The crude protein obtained in this study was lower than the reported by earlier researchers, which may be due to the low amount of rainfall during the vegetation stage and planted in autumn.
 
Seed crude protein (%)
 
Although, the crude protein in seed did not vary due to different sowing times, however, the highest protein content was measured in December 15 sowing plots (34.86%) (Table 2). According to the result of studies carried out with white lupine (Lupinus albus L.) with different genotypes in different ecologies, the protein content in white lupine seeds were found to be ranging from 24.90 to 33.30%. Erbaþ et al., (2005) found the protein content in white lupine seeds in Antalya as 32.20%. Yorgancýlaret_al(2007) measured the protein content in the seed in the local lupen populations in Konya as 32.45%. However, Georgieva et al., (2018) reported the proportion of crude protein in seeds in Plevne between 24.90 and 33.30%.