Impaginato 177 Adv. Hort. Sci., 2018 32(2): 177-183 DOI: 10.13128/ahs-21898 Poultry manure application time on pistachio (Pistacia vera L.) trees M.J. Mahmoudi Meimand 1 (*), M.H. Shamshiri 2, H.R. Roosta 2, E.U. Khan 3 1 Department of Horticulture, Agri-College, Vali-e-Asr University of Rafsanjan, Iran. 2 Department of Horticulture, Vali-e-Asr University of Rafsanjan, Iran. 3 Nuclear Institute for Agriculture and Biology (NIAB), Faisalabad, Pakistan. Key words: nutrients, organic matter, pistachios, poultry manure, yield elements. Abstract: The effectiveness of poultry manure application time was studied on pistachios (Pistacia vera L.) trees. The experiment consisted of seven different poultry manure application time, including poultry manure application as one time in 1) last week of October 2) last week of December 3) last week of January 4) mid-March and dividing into two parts and use in fall or in winter, dividing into four parts and use in dormant seasons (fall and winter). Based on the results, there were significant differences among treatments. The highest number of fruit per cluster (27.4) was found in poultry manure applied in last week of October. The highest nut splitting percent (84.3%) and the lowest nut blanking percent (8.6%) were obtained in poultry manure applied by dividing into four parts. Half kernel nuts followed a similar trend with blanking percent. Weight of 1000 nuts increased and responded positively and number of pista- chios nut per ounce decreased by manure application when divided into two parts and used in the winter. Application of poultry manure in the mid-March enhanced the nut protein (19.63%). 1. Introduction Production technologies of horticultural crops including pistachio tree have undergone vast changes recently, and led to the extension of innov- ative technologies about nutrient management. The critical factor of nutrient management of nut trees like pistachio is to elevate the net yield and improve the quality of nut fruits. Pistachio blanking and flower bud abscission can be directly related to nutrition management (Mahmoudi Meimand and Ghanbari Odivi, 2013). Nowadays, fertilizers play a key role in nutrition of fruit trees. Because of harmful side effects of chemical fer- tilizers, (Ljoyah and Sophie, 2009) the use of bio fertilizers are increasing recently. Organic fertilizers, such as animal manure, have a long history of use by men (BayBordi and Malakuoti, 2003). Different animal manures such as sheep, cow and poultry manures have been used as natural crop (*) Corresponding author: mmeimand@ut.ac.ir Citation: MAHMOUDI MEIMAND M.J., SHAMSHIRI M.H., ROOSTA H.R., KHAN E.U, 2018 - Poultry manure application time on pistachio (Pistacia vera L.) trees - Adv. Hort. Sci., 32(2): 177-183 Copyright: © 2018 Mahmoudi Meimand M.J., Shamshiri M.H., Roosta H.R., Khan E.U. This is an open access, peer reviewed article published by Firenze University Press (http://www.fupress.net/index.php/ahs/) and distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Data Availability Statement: All relevant data are within the paper and its Supporting Information files. Competing Interests: The authors declare no competing interests. Received for publication 10 October 2017 Accepted for publication 12 January 2018 AHS Advances in Horticultural Science Adv. Hort. Sci., 2018 32(2): 177-183 178 fertilizers for centuries. Poultry manure, because of its high level of nitrogen which is absorbable for pis- tachio trees, has been recognized as one of the main favorable manures. It has been documented that poultry manures also supply other essential pistachio nutrients and act as soil amendant by raising organic matter content, which helps improve the moisture level of soil and nutrient maintenance. According to Alimoradi (2011) nearly 5.3 million tons of poultry manure is consumed in Rafsanjan and Kerman pista- chio orchards every year. These bio fertilizers are known as main source of manure for Iranian pista- chio growers. Nutrients provided by poultry manures have been indicated to establish effects on different crops, including fruit crops (Mitchell et al., 1993; Miller, 1996). It has been reported that poultry manure is composed of essential elements for fruit crops containing about 3% of nitrogen NH4 +, 63.2% phosphorus P2O5 and 4.1% potassium K2O (Reddy and Reddy, 1995). The main form of nitrogen in poul- try manures is NH4 +, which elevate the availability of nitrate to the plants for a longer period (Burmester, 1993; Crawford and Chalk, 1993; Touchton and Bosewell, 1980). On the other hand, organic manures application to decrease the use of chemical fertilizers in pistachio orchards and other fruit trees is an important goal in fruit production (Reganold et al., 2001; Forge et al., 2002). Organic manures increase the fertility of soil and the crop yield. Therefore, they can be helpful to achieve sustainable agriculture. It has been demonstrated earlier that poultry manure improved growth parameters, yield and quality in dif- ferent crops (Ram and Rajput, 2002; Ingle et al., 2003; Arancon et al., 2003). Pimpini et al. (1992) revealed higher rate of ex-tractable sucrose by using 4 t ha-1of poultry manure in crops. Increased content of total carbohydrate, protein and ascorbic acid were reported by Abusaleha and Dutta (1988) when poul- try manure was used. Improving photosynthesis, plant biomass and glycosides content of Stevia were also demonstrated before (Xiangyang et al., 2010). Enhanced starch content, crude fiber, ash, crude pro- tein, phosphorus, calcium and magnesium of D. bulb- ifera were reported by Ezeocha et al. (2014). Adekiya and Agbede (2017) showed that poultry application increased soil organic matter, leaf N, P, K, Ca, Mg contents, growth and yield in tomato. They also showed that the application of poultry manure at 3 weeks before transplanting had highest effects on leaf nutrient concentrations, growth and yield in tomato (Adekiya and Agbede, 2017). Now, pistachio growers are frequently using poultry manure as a source of plant nutrient. To our knowledge, there are no reports available to recommend favorable time for poultry manure application in orchard of pista- chio trees. The aim of this investigation is to study the effect of poultry manure application time on nut yield and quality in pistachios trees. 2. Materials and Methods The experimental orchard selected for this study is located at Khatam, Yazd province, Iran. It is located at 39.33°N latitude and 54.40°E longitudes, at an ele- vation of 1605 m above sea level. The average tem- perature of the zone is 18.5°C, the annual total chilling hours (≤7.2°C) is about 950; the average annual rainfall is 300 mm. The climate of this area is typically subtropical. Just before poultry manures application, soil sample of the experimental orchard were collected and chemically analyzed (Table 1). This research was conducted on 12 years old pista- chio cv. Akbari grafted on ‘Badamii Zarand’ rootstock. Management factors such as irrigation regime, prun- ing practices, and weed control were followed according to local standards. Trees were trained with a modified central leader system and distance of trees was 2x6 m. To achieve better results, uniform trees were selected with uniform vigor and age and three uniform shoots were selected from different sides of the tree for data collection. Harvest index was considered when several nuts in the cluster were light colored and the hull was easily separated from shell. Characteristics of yield, percentage of splitting, weight of 1000 nuts, blanking, pistachio weight in Soil characteristics Value pH 7.6 EC ds m-1 4 P ppm 28.1 K ppm 180 O.M. % 1.3 T.N.V. % 22.1 Sand % 52 Silt % 34 Clay % 14 Texture Loam ESP 17.9 Table 1 - Soil fertility analysis report of the experimental orchard Mahmoudi Meimand et al. - Poltry manure application on pistachio trees 179 ounce, dry weight and some other characteristics related to kernel and leaf were recorded. The experi- ment consisted of seven different poultry manure application time, with three replications based on the Randomized Complete Block Design (RCBD). The treatments were poultry manure application as one time in 1) last week of October 2) last December 3) last week of January 4) mid-March and dividing into two parts and use in fall or in winter, dividing into four parts and use in dormant seasons (fall and win- ter). These treatments were conducted beneath the tree canopy and mixed well with surface soil, 10 kg per tree. Data collecting was performed in next growth season. Statistical analysis was conducted using the SAS software (9.2) and means were com- pared by Duncan’s Multiple Range test (P≤ 0.05). 3. Results and Discussion Effect of poultry manure application time on yield parameters Number of fruits per cluster. The study indicated that poultry manure application time had significant effects on number of fruits per cluster (P≤ 0.05) (Table 2). The highest number of fruit per cluster was found by poultry manure application in last week of O c t o b e r ( 2 7 . 4 ) f o l l o w e d b y t h e l a s t w e e k o f December (26.9) (Table 2). The minimum value (19.2) was observed in control treatment. The higher fruit per cluster with poultry manure application in last week of October (concurrently with tree deciduous) might be related with the positive role of nitrogen and other critical elements on cluster final develop- ment. Burmester (1993) Crawford and Chalk (1993) Touchton and Bosewell (1980) demonstrated the positive role and proportion ratio of elements on reproductive growth parameters. Nut splitting percent. Also, our results demon- strated that poultry manure application time had sig- nificant effects on nut splitting percent (Table 2). Highest nut splitting percent (84.3%) was obtained in treatment of poultry manures divided into four parts and used in last weeks of October, December, January and mid-March followed by divided into two parts and used in fall (83.5%) and in winter (83.1%) (Table 2). The minimum value for nut splitting per- cent was reported in control treatment. Based on our results, the poultry manure application in four differ- ent times, thus involving a longer period of the year improved nut splitting percent. It has been demon- strated before that poultry manure was improved yield quality in different crops (Arancon et al., 2003; Ingle et al., 2003). Number of pistachio nuts per ounce. Table (2) indi- cates that the use of poultry manure increased the pistachio ounce index or decreased number of inshell pistachio nuts per ounce significantly (P≤ 0.01). The results showed also that when a portion of poultry manure is allocated at the end of dormant season, increase fruit size is achieved. Previous findings showed that poultry manure improved yield compo- nent in different crops (Ram and Rajput, 2002; Arancon et al., 2003). Blanking percent. Based on the results, the lowest value (8.6%) for nut blanking was observed when treatment consisted in dividing poultry manures into four parts and usi ng i n l ast weeks of October, December, January and mid-March; this was fol- lowed by treatment divided into two parts and used in winter (11%) (Table 2). The maximum amount of blanking (%) was observed in control treatment (13.9%) with no significant difference with fall appli- cation. Therefore, poultry manure application at over the year in four different times decreased nut blank- ing percent. Yield component improving demonstrat- lwo= last week of October, lwd= the last week of December, lwj= the last week of January, Mm= March mid, lwjm= divided into two parts and used in the winter, lwod= divided into two parts and used in the fall, lwodjm= poultry manures divided into four parts and used in the last week of October, the last week of December, the last week of January and March mid. Means followed by the same letters are not significantly different (Duncan test, P≤ 0.05). Parameter\treatment lwo lwd lwod lwj Mm lwjm lwodjm control Number of fruit 27.4 a 26.9 b 22.6 c 21.2 e 21.05 e 22.1d 26.9 b 19.2 f Nut splitting % 77.3 b 76.4 b 83.5 a 70 c 69.8 c 83.1 a 84.3 a 64.8 d Fruit ounce 22.6 a 22.6 a 22 ab 22.6 a 22.3 a 20.6 b 20.6 b 23 a Blanking % 13.3 ab 13.5 ab 13.1 bc 12.5 bc 12.8 bc 11 d 8.6 e 13.9 a Half seed fruit % 1.3 c 1.2 d 0.7 e 4.4 b 3.1 c 0.9 e 0.7 e 5.0 a Weight of 1000 nuts 1249 b 1249 b 1288 b 1249 b 1267 b 1372.1 a 1370 a 1231 b Table 2 - Effect of poultry manure application time on yield parameters Adv. Hort. Sci., 2018 32(2): 177-183 180 ed by Ram and Rajput (2002) and Arancon et al. (2003). Half kernel fruit percent. Half kernel nuts followed a trend similar to blanking percent, it was decreased with dividing poultry manure into four parts (0.7%), followed by manure divided into two parts and used in fall (0.7%) or winter (0.9%) (Table 2). The highest half kernel nuts percent was obtained in control (Table 2). W e i g h t o f 1 0 0 0 n u t s . W e i g h t o f 1 0 0 0 n u t s increased and positively and significantly (P>0.05) responded to the treatments. Highest weight of 1000 nuts (1372.1 g) were observed in poultry manure divided into two parts and applied in winter followed by treatment consisting in manure divided into four parts and used in last weeks of October, December, January and mid-March (1370 g). However, other treatments exhibited lowest weight of 1000 nuts (Table 2). Previous findings indicated that poultry manure improved yield component in different crops (Ram and Rajput, 2002; Arancon et al., 2003). Effect of poultry manure application time on nut quality parameters Fruit stening. Fruit stening was influenced by application of poultry manure in different times (Table 3). Maximum amount for fruit stening (7.23%) was noted at mid-March application (7.23%) and con- trol (7.16%) and the lowest value for this parameter was obtained with treatment divided into two parts and used in fall treatment (Table 3). It has been demonstrated earlier that poultry manure improved yield and quality in different crops (Ram and Rajput, 2002; Arancon et al., 2003; Ingle et al., 2003). N u t p r o t e i n . N u t p r o t e i n s p e r c e n t w a s a l s o enhanced by the application of poultry manure in all treatment versus control (Table 3), but maximum value for nut protein percent was observed at mid- March (Mm) application (19.63%) followed by the last week of January (19.5%) and in poultry manures divided into four parts and used in last weeks of October, December, January and mid-March (19.2%) with no significant differences (Table 3). The mini- mum value for nut protein percent was observed in control treatment (17.4%). Increasing amount of total carbohydrates, proteins and ascorbic acid con- tent reported by Abusaleha and Dutta (1988) in a similar work that well described poultry manure application on increasing secondary metabolites. Enhancing crude protein in D. bulbifera was reported by Ezeocha et al. (2014). The results reported by Adekiya and Agbede (2017) showed that poultry application produced higher percent protein content, more growth and yield in tomato. Effect of poultry manure application time on vegeta- tive and reproductive parameters Leaf fresh weight. According to obtained results, poultry manure application time had significant effects on leaf fresh weight (P≤ 0.05) (Fig. 1). The highest amount of leaf fresh weight was obtained at poultry application in mid-March (2.1 g), followed by Fig. 1 - Changes of leaf fresh (x) and dry weight (■) (gr) of pista- chio (P. vera cv. Akbari) grown in Khatam, Yazd, Iran. Duncan was calculated at P≤0.05. lwo= last week of October, lwd= last week of December, lwj= last week of January, Mm= March mid, lwjm= divided into two parts and used in the winter, lwod= divided into two parts and used in the fall, lwodjm= poultry manures divided into four parts and used in the last week of October, the last week of December, the last week of January and March mid. Parameter\treatment lwo lwd lwod lwj Mm lwjm lwodjm control Fruit stening (%) 5.6 d 6.56 b 4.2 f 6.8 b 7.23 a 5.9 c 4.96 e 7.16 a Nut protein (%) 19.1 bc 19 c 18.9 c 19.5 ab 19.63 a 19.2 ab 19.2 ab 17.4 d Table 3 - Effect of poultry manure application time on nut quality parameters lwo= last week of October, lwd= the last week of December, lwj= the last week of January, Mm= March mid, lwjm= divided into two parts and used in the winter, lwod= divided into two parts and used in the fall, lwodjm= poultry manures divided into four parts and used in the last week of October, the last week of December, the last week of January and March mid. Means followed by the same letters are not significantly different (Duncan test, P≤ 0.05). Mahmoudi Meimand et al. - Poltry manure application on pistachio trees 181 application divided into two parts and used in winter (1.9 g) (Fig. 1). The lowest rate of leaf fresh weight was occurred in control (1.5 g) and last week of October (1.5 g), respectively (Fig. 1). Based on our result, poultry manure application in mid-March at once increased leaf fresh weight. Increasing photo- synthesis and plant biomass of Stevia was also demonstrated before (Xiangyang et al., 2010). Leaf dry weight. Dry weight of leaves was signifi- c a n t l y a f f e c t e d b y d i f f e r e n t t i m e s o f m a n u r e application (P≤ 0.05). Maximum leaf dry weight was found in poultry application in mid-March (0.8 g) and divided into two parts and used in winter (0.8 g), whereas the minimum was observed in control (0.4 g) and last week of October (0.4 g) (Fig. 1). This increase in leaf dry and fresh weights with applica- tion of poultry manures at the end of dormant sea- son can be explained as following, this time of appli- cation cannot make the expected effect and causes to increase vegetative parameters, similar to reports published by Xiangyang et al. (2010). Leaf nitrogen content. Results revealed that the leaf nitrogen content of pistachio trees fertilized with poultry manure in different times varied significantly (P≤ 0.05). Leaf nitrogen content was the highest (3.1%) at poultry application in mid-March once at any time compared to the treatments divided into two parts and applied in winter (3.03%) and in last week of January (2.9%) (Fig. 2). The higher leaf nitro- gen content in mid-March application of poultry manures could be in relation with releasing more nitrogen NH4 + form which is useful for vegetative parameters and causes nitrogen accumulation in the leaves. Previous findings emphasis on high level of NH4 + form in poultry manure. The application of poul- try manure with high level of N, have influenced the growth and vegetative factors of tree and production of fruits (Reddy and Reddy, 1995). Adekiya and Agbede (2017) indicated that application of poultry manure increased percent of leaf N, P, K, Ca, Mg con- tent, growth parameters and yield in tomato. Poultry manure usage at 3 weeks before transplanting caused higher leaf nutrients concentrations and more growth and yield in tomato (Adekiya and Agbede, 2017). Shoot length. Based on our findings, shoot length was significantly affected by different application times of manure (P≤0.05). Maximum shoot length was obtained when manure was divided into two parts and used in winter (44 cm) and mid-March application (43.3 cm). Our results revealed that mini- mum value for this parameter was observed in con- trol (26.6 cm) and in manure divided into two parts and used in fall (32.6 cm) (Fig. 3). Similar to the dry and fresh weights, application of poultry manures at the end of dormant season caused to increase shoot length. Our results demonstrated that application of poultry manures during fall stimulates a least vegeta- tive growth with no significant differences between various times in fall (Fig. 3). Increasing vegetative growth and similar findings by using poultry manure Fig. 2 - Changes of leaf nitrogen content of pistachio (P. vera cv. Akb a ri ) gro wn i n Kh a t a m, Y a z d , I ra n . D u n ca n wa s calculated at P≤0.05. lwo= last week of October, lwd= last week of December, lwj= last week of January, Mm= March mid, lwjm= divided into two parts and used in the winter, lwod= divided into two parts and used in the fall, lwodjm= poultry manures divided into four parts and used in the last week of October, the last week of December, the last week of January and March mid. Fig. 3 - Changes of shoot length of pistachio (P. vera cv. Akbari) grown in Khatam, Yazd, Iran. Duncan was calculated at P≤0.05. lwo= last week of October, lwd= last week of December, lwj= last week of January, Mm= March mid, lwjm= divided into two parts and used in the winter, lwod= divided into two parts and used in the fall, lwodjm= poultry manures divided into four parts and used in the last week of October, the last week of December, the last week of January and March mid. Adv. Hort. Sci., 2018 32(2): 177-183 182 have been reported before (Xiangyang et al., 2010). Leafy bud number, floral bud number and leafy to flower bud ratio. Results indicated that leafy and flo- ral buds and leafy to flower bud ratio of pistachio trees fertilized with poultry manure was positively affected by treatments (P≤ 0.05). Number of floral buds in the next growing season was the highest in last week of October and fall (in last weeks of October and December) (7.33) (Fig. 4). Minimum value for floral bud number was observed in control (Fig. 5). Results for leafy bud numbers showed that maximum value was obtained in treatment divided into two parts and applied in winter (5.6) and mid- March (5.3) (the letter two treatments have not any significant difference) (Fig. 4). Floral bud abscission ratio. It was revealed that floral bud abscission during the grow season by poul- try manure usage was significantly less than control, which it might be due to the role of poultry manure in decreasing floral bud abscission totally. Any treat- ment could not show significant effect on floral bud abscission, but minimum amount for this parameter was observed in treatment that was conducted in last week of December (0.32) (Fig. 5). Previous reports showed that poultry manure improves the yield component (Ram and Rajput, 2002; Arancon et al., 2003), although there are no exact results about reproductive phase and parameters affected by poul- try manure treatment, but flower bud abscission can b e d i r e c t l y r e l a t e d t o n u t r i t i o n m a n a g e m e n t (Mahmoudi Meimand and Ghanbari Odivi, 2013). 4. Conclusions It is clear that application of organic fertilizers will improve the nut yield and quality, but application of poultry manure through dormant season can be effective on reproductive and vegetative parameters in pistachio. Based on our findings, dividing poultry manures into four parts and applying in last weeks of October, December, January and Mid-March, or using a single application in fall showed the best results for optimum nut yield, quality and floral bud emergence in pistachio. References ABUSALEHA, DUTTA O.P., 1988 - Inter relationship of yield components in cucumber. - Veg. 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