Pistachio Rootstocks Influence Scion Growth and Ion Relations under Salinity and Boron Stress

Abstract

<jats:p>Performance of `Kerman' pistachio (<jats:italic>Pistacia vera</jats:italic> L.) trees on three rootstocks (<jats:italic>P. atlantica</jats:italic> Desf., <jats:italic>P. integerrima</jats:italic> Stewart and `UCB-1', a <jats:italic>P. atlantica</jats:italic> × <jats:italic>P. integerrima</jats:italic> hybrid) was evaluated with 2-year-old trees grown in sand-tank lysimeters under combined SO<jats:sub>4</jats:sub><jats:sup>2-</jats:sup> and Cl<jats:sup>-</jats:sup> salinity and boron (B) stress for 6 months. Four salinity treatments were imposed by irrigating the plants with water at electrical conductivity (EC<jats:sub>iw</jats:sub>) of 3.5, 8.7,12, or 16 dS·m<jats:sup>-1</jats:sup> each containing B at 10 mg·L<jats:sup>-1</jats:sup>. Growth of `Kerman' was evaluated based on increase in total leaf area, increase in trunk diameter, and total above-ground biomass production. All growth parameters decreased as salinity increased, but were not significant until EC<jats:sub>iw</jats:sub> exceeded 12 dS·m<jats:sup>-1</jats:sup>. However, growth of `Kerman' on <jats:italic>P. atlantica</jats:italic> and `UCB-1' was considerably better than on <jats:italic>P. integerrima</jats:italic> at 16 dS·m<jats:sup>-1</jats:sup>. The onset and severity of foliar injury differed among scions and treatments and was attributed primarily to B toxicity, rather than the effects of salinity. Concentrations of B in injured leaf tissue ranged from 1000 to 2500 mg·kg<jats:sup>-1</jats:sup>. Leaf injury decreased with increasing salinity, although leaf B was not significantly reduced suggesting an internal synergistic interaction between B and other mineral nutrients. However for <jats:italic>P. vera</jats:italic> on <jats:italic>P. integerrima</jats:italic>, the highest level of salinity produced the greatest injury, possibly as a combination of B plus Cl<jats:sup>-</jats:sup> and/or Na<jats:sup>+</jats:sup> toxicity. Leaf transpiration, stomatal conductance, and chlorophyll concentration of <jats:italic>P. vera</jats:italic>, determined by steady-state porometry, were also reduced to a greater degree by combined salinity and B when budded on <jats:italic>P. integerrima</jats:italic> than on the other two rootstocks.</jats:p>

Effect of Salinity and Nitrogen Application on Growth, Chemical Composition and Some Biochemical Indices of Pistachio Seedlings (Pistacia Vera L.)

“…Although pistachio trees are classified as moderately salt-sensitive crop (Maas and Grattan, 1999), the ability to tolerate adverse water quality creates a niche for pistachio in areas where soils are saline or where saline or moderately saline water supplies are used for irrigation (Ferguson et al, 2002). Among the macronutrients, nitrogen (N) is the most widely needed fertilizer element in pistachio and plays a vital nutritional and physiological role in plants.…”

Growth, chemical composition, and carbon isotope discrimination of pistachio (Pistacia vera L.) rootstock seedlings in response to salinity

“…Poor quality of irrigation water in association with sodic soils has reduced yields of pistachio over recent years, especially in the south-east of Iran in Kerman, and in central Iran, particularly in the Yazd and Qhom regions. Despite reduced yields with increasing salinity, pistachio has been described as salt tolerant (Sepaskhah and Maftoun 1981;Behboudian et al 1986;Picchioni and Miyamota 1990;Ferguson et al 2002) and is potentially an alternative to salt-sensitive pecan (Carya illionsis) or almond (Prunus amygdalus). However, symptoms of toxicity in pistachio and cultivar differences in susceptibility to salinity have been previously described (Sepaskhah and Maftoun 1981;Behboudian et al 1986;Picchioni and Miyamota 1990;Ferguson et al 2002).…”

“…Despite reduced yields with increasing salinity, pistachio has been described as salt tolerant (Sepaskhah and Maftoun 1981;Behboudian et al 1986;Picchioni and Miyamota 1990;Ferguson et al 2002) and is potentially an alternative to salt-sensitive pecan (Carya illionsis) or almond (Prunus amygdalus). However, symptoms of toxicity in pistachio and cultivar differences in susceptibility to salinity have been previously described (Sepaskhah and Maftoun 1981;Behboudian et al 1986;Picchioni and Miyamota 1990;Ferguson et al 2002). For example, saline stress can cause decreased growth, alter photosynthetic rates, and causes morphological change in the leaves (Behboudian et al 1986;Picchioni and Miyamota 1990;Ranjbar et al 2002;Munns et al 2002).…”

“…Most attempts to correlate growth of different pistachio rootstocks with the physiological effects of salinity have been made on young seedlings at a single harvest date (Sepaskhah and Maftoun 1981;Behboudian et al 1986;Picchioni and Miyamota 1990;Ferguson et al 2002). These comparative studies can be misleading because they do not consider the initial biomass of the plant, which can influence subsequent growth rates and final size at harvest (Ruiz et al 1997).…”

Osmotic stress affects physiological responses and growth characteristics of three pistachio cultivars

“…Drought tolerance of wild pistachio species could be related to a deep taproot, high water conservation ability by stomatal adjustment, stomatal features, leaf characteristics, and leaf shedding (Fardooei 2001;Germana 1996;Spiegel-Roy et al 1977). Therefore, these wild species are very often used as rootstock (Ferguson et al 2002;Ranjbarfordoei et al 2002). Germana (1996) found that midday xylem water potentials of plants grafted on P. atlantica or P. terebinthus did not drop below -0.5 MPa under drought and explained this by their deep, expanded root systems.…”