Sustainable Produce of Red Plum Apricot in Water-Limited Regions 1

Sustainable Produce of Red Plum Apricot in Water-Limited Regions 1 Zhongsheng Guo 2 3 Institute of Soil and Water Conservation, Northwestern AF University, Chinese Academy of 4 Sciences and Ministry of education, 5 Yangling, China 6 *Correspondence author’s email address: 26#, Xinong Road, 7 Yangling, 8 Shaanxi Province 712100, 9 P. R. China 10 11 Correspondence author’s Tel. ++86-29-87012411 ; 12 Correspondence author’s Fax. ++86-29-8701-2210 13 *Correspondence author’s email address: zhongshenguo@sohu.com 14 15 Abstract: Red plum apricot is the best apricot over the world. Since having been introduced into 16 Guyuan county in 1987 from Shaanxi province, red plum apricot grows well and then has been 17 selected as good varieties to popularize in semirid loess hilly regions because the color of red 18 plum apricot is beautiful, aroma fragrant , and taste is the mix of sour and sweet and nutrition is 19 rich. Since 1995, the yield, benefits and planting area of red plum apricot increase doubly, and the 20 distribution range of red plum apricot increased from Guyuan to the whole Ningxia, and then to 21 Gansu province and so on in the water-limited regions, China. However,there are still some 22 Preprints (www.preprints.org) | NOT PEER-REVIEWED | Posted: 26 August 2019 doi:10.20944/preprints201908.0270.v1

problems in the sustainable produce of red plum apricot. In order to promote the development of 23 red plum apricot and meet people's increasing demand，we should do intensive study of the 24 relationship between red plum apricot and environment and the comparison of possible methods to 25 reduce the bad influence of drought, low temperature and frost on quality and production of red 26 plum apricot, and determine the soil water resources use limit by red plum apricot and the suitable 27 leaf amount of red plum apricot when the planting density equal soil water carrying capacity for 28 red plum apricot and select the best method to reduce or evade the bad influence of soil drought, 29

Introduction 35
The apricot (Prunus armeniaca L.) is a member of the Rosaceae, with subfamily 36 of Prunoideae. Apricot which it is used as fresh, dried or processed fruit, is rich in 37 many plant antioxidants and a good source of dietary fiber. Of the applications of 38 apricot in food technology are producing dried fruit, frozen apricot, jam, jelly, 39 marmalade, pulp, juice, nectar, extrusion products and so forth. Also, apricot is an 40 economic fruit because its kernel is used for making oils, benzaldehyde, cosmetics, In most parts of the world, human activities, such as overgrazing, deforestation,denudation and 46 reclamation have greatly altered the type of vegetation that dominates the landscape. These have 47 accompanied the demand for food, fruit, timber and biofuels due to local population increases, 48 which historically have frequently occurred in water-limited regions (Metcalfe and Kunin, 2006), 49 such as the Loess Plateau of China ( Guo and Shao, 2013). Since the 1949, with the increase of 50 population, the most of land changed into farm land to produce food and meet the people's 51 increasing demand with people population increase. As a result, the native vegetation is destroyed 52 irrationally, but the food yield is low, about 150 to 200 per Mu (Mu is Chinese area unit, 1 Mu = 53 666.7 m 2 ) and not stable, and not enough to meet the need of people for food. At the same time, 54 the soil and water loss is serious and soil degrades because the soil loss modulus is between 5000 55 to 10000 t per square kilometer. In order to change this situation, increase people 's income and 56 carry out sustainable development, since 1983, many economic forest species , such as red plum 57 apricot, were introduced from Shaanxi fruit institute, China and planted in the Shanghuang 58 Eco-experimental Station and have been compared and analysed in the same site condition. In 59 1995, red plum apricot was selected and promoted and developed fast after 1995. Red plum 60 apricot not only promoted the development of local industry development, but there are also some 61 problems need to be solved. In order to promote the development of apricot industry, the purpose 62 of this study was to review the development of red plum apricot and find and overcome some limit 63 factors of the development of the apricot and promote the sustainable produce of red plum apricot. 64

Introduce of red plum apricot into the semi-arid region of the Loess Plateau 65
The Shanghuang Eco-experimental Station was located in the semi-arid region of the Loess 66 Plateau, in the Eastern 20 Km from Guyuan County, in the Ningxia Hui Autonomous Region of 67 western China, see fig.1. The area is located in a hilly loess region with an elevation range of 68 1,534 to 1,824 m and slope gradients of 0˚ to 10˚ and the slope gradients below the valley shoulder 69 line is more than 25˚. The main soil type is Huangmian soil (Calcaric Cambisol, FAO 1988) that is 70 developed from loess and is susceptible to soil and water losses, which are serious in this region. 71 The rainfall is unevenly distributed in the year with a mean annual precipitation of 416 mm, and 72 rainfall from June to September accounts for 64.7 % of the total annual precipitation. The 73 coefficient of variation of precipitation among the years from 1983 to 2001 was 23.8% and rainfall 74 amounts ranged from 259.9 mm in 1991 to 634.7 mm in 1984, with a median rainfall amount of 75 434 mm. Mean solar radiation is 5, 342 MJ m 2 ; annual average temperature is 7.0˚C. Plant 76 growing period is 152 days. Groundwater level is more than 60 meters (Guo and Shao, 2013). 77 Low temperature, frost and drought are the main disaster weather which influence sustainable 78 produce of red plum apricot. Since red plum apricot introduced in 1988 from Shaanxi province to 79 the Shanghuang Eco-experimental Station. 80 The root stock of red plum apricot is Armeniaca sibirica (L.) Lam, which means that Red plum 81 apricot grafted on apricot. In the red plum apricot plantation, 3 trees was selected as sample. In 82 every sample tree, 9 branches at different direction was selected and hang tag to investigate the 83 base diameter and height growth with a 10 day interval from April to October in the growing 84 season. The size and qaulity of red plum apricot fruit was measured and tasted. And then analyse 85 the change of red plum apricot growth with time and the quality and yield of red plum apricot 86 Shi, 1993；Shi andGuo 1995). 87

Breeding and popularization of red plum apricot 88
In the Shanghuang Eco-experimental Station, red plum apricot grows well. The shape of red 89 plum apricot fruit is about round and looks beautiful. The size of fruit is big, see selected and popularization because red plum apricot fruit is mature early, and fruit is larger, and 96 quality is high, and production is stable (Shi and Guo, 1995;Guo 2013). Some 3-years-old Red 97 plum apricot begins to bears fruit, and 4-years-old Red plum apricot obtain higher yield planting 98 in the station. It starts to germinate in March 28 (Guo and Si, 1993) and expand leaf in the middle 99 of April. Red plum apricot blooms from late March to early April and blooms, and bears fruit in 100 mid-April. Fruit ripes in the early July in the eco-experiment station, Guyuan County in the 101 Ningxia Hui Autonomous Region. Red plum apricot is used as fresh food as well as raw material, 102 such as making dried fruit by wind-drying. 103 In 2008, we found the serious influence of a heart-eating insects (grapholitha molesta (Busck) 104 on fruit quality, 67% of red plum apricot fruit of 100 kg was suffer the pest injury, which has the 105 most pest influence on the qaulity of red plum apricot. We select the high efficiency cypermethrin, 106 a kind of efficient and Low toxicity pesticide on the Red plum apricot and selected 28 red plum 107 apricot as sample tree and spraying red plum apricot with 2000 times high efficiency cypermethrin 108 in the period from May 20 to 27 in apricot garden of the eco-experiment station . The fruit eaten 109 by heart-eating decreased to 1/1000. Because the cypermethrin is high efficiency and low toxin,

Sustainable Produce of red plum apricot 125
Although Red plum apricot is anty-drought, anty-cold and anty-frost, the high-yield , 126 high-benefit plantation not only bear fine fruit, increase income of farmer, fix carbon dioxide, 127 improve and beautify ecological environment, but in the process of plantation in the water-limited 128 regions, sometime soil desiccation often occurs and quickly changes into severe desiccation and 129 causes soil degradation and part branches or whole tree death, which waste soil water resources 130 and influence the Sustainable Produce of red plum apricot because as plant grow，the Branch and 131 leaf quantity of canopies is increasing，which increase the canopies interception and soil water 132 consumption and reduce the soil water supply . Low temperature and frost often happens in the 133 period of Red plum apricot flowering because of low temperature and frost. The soil desiccation, 134 low temperature and frost will reduce the quality, yield and economic benefits in the water-limited 135 regions, so it is necessary to take effective method to reduce the influence of drought, low 136 temperature and frost on the quality and yield of Red plum apricot. 137 In order to protect the germplasm resource of red plum apricot and promote the development fruit tree growth and soil water can be regulated by changing the amount of tree or plant (Guo,153 2014), as for some plant, such as red plum apricot, the relationship often can be regulated by 154 cutting some of vimens or leaf or fruit in the key regulating period within fruit expansion period 155 because the relationship between fruit tree growth and soil water has to be regulated by changing 156 the amount of vimens or leaf or fruit. 157 According to the study in 2018, the maximum infiltration depth is 290cm, and wilting 158 coefficient varies with soil depth from 7.98 in surface soil to 7.1% in 240 cm soil depth, and the 159 soil water resources use limit by red plum apricot is 212.7 mm. The soil water resources in the 160 maximum infiltration depth in the growing season for the 1-year-old red plum apricot and 161 23-year-old red plum apricot is more than the soil water resources use limit by Red plum apricot 162 of 212.7 mm, and red plum apricot grow well, so, we do not need to regulate the red plum apricot 163 because the precipitation in 2018 is 536.2 mm, which is 120.6 mm more than the mean 164 influence the plant growth. Two curves method was used to estimate infiltration depth and soil 188 water supply for a rain event ( Guo, 2004). A series of two curves methods for maximal infiltration 189 depth for a long time infiltration process (Guo and Shao 2009, Guo 2014, 2017. region because water resources is lack. In order to effectively reduce the influence of low 204 temperature and frost on the quality and yield of red plum apricot, we should compare the possible 205 method, such as smoke method, Spraying antifreeze or water and so on，and select best measure to 206 use. 207

Conclusion 208
Red plum apricot is one of the best fruit and food in the world. In the near future, planting area 209 of red plum apricot area will enlarge and we should do intensive study of the relationship between 210 red plum apricot production and environment and determine the soil water carrying capacity for 211 red plum apricot and compare possible methods to reduce the influence of drought, low 212 temperature and frost on the quality and yield of red plum apricot, and then take the appropriate 213 method to regulate the relationship between red plum apricot growth and soil water or reduce or 214 evade the bad influence of low temperature, frost and soil drought to ensure the sustainable 215 produce of red plum apricot. 216 In a word, we should continue to increase the planting area and enlarge the distribution range 217 of red plum apricot to produce more red plum apricot fruit to meet the increasing need of urban 218 residents for fine red plum apricot fruit. At the same time, we should increase the income of 219 farmer who plant red plum apricot in countryside under the condition of keeping sustainable use 220 of nature resources and sustainability of fine environment to realize sustainable development. 221