Stomatal response to leaf water potential in almond trees under drip irrigated and non irrigated conditions

Almond plants (Amygdalus communis L. cv. Garrigues) were grown in the field under drip irrigated and non irrigated conditions. Leaf water potential () and leaf conductance (g₁) were determined at three different times of the growing season (spring, summer and autumn). The relationships between and g₁ in both treatments showed a continuous decrease of g₁ as decreased in spring and summer. Data from the autumn presented a threshold value of (approx. –2.7 MPa in dry treatment, and approx. –1.4 MPa in wet treatment) below which leaf conductance remained constant.     

Odor, taste, and flavor perception of some flavoring agents

Psychophysical functions for the odor, taste, and flavor offive common flavorings were obtained by the method of magnitudeestimation. The stimuli included three simple compounds (vanillin,piperonal, and benzaldehyde) and two complex ones (natural vanillaextract and artificial almond essence). The odor intensity ofall the flavorings grew much less rapidly with concentrationthan did taste intensity. The growth of flavor for the complexsubstances and piperonal behaved very much like taste. For vanillinand benzaldehyde, the flavor functions resembled taste functionsat high concentrations but showed a tendency to flatten at lowerconcentrations. These findings implied that, at least for someflavorings, the growth of flavor reflects the most salient featureon the particular concentration range studied. At low concentrationsodor seems to be the most important feature and so flavor functionsare generally flat, but at high concentrations taste becomesthe salient feature and so flavor functions steepen.     

苦杏仁精油对粘虫的触杀活性研究

以粘虫4龄幼虫为对象,采用"点滴法"研究了山杏种仁两种苦杏仁精油(含HCN和去HCN)对粘虫的触杀活性及其生长发育的影响.结果显示,处理后48 h,5～100 μL/mL浓度处理的试虫死亡率均在51.67%以上,40和100 μL/mL浓度处理的粘虫死亡率分别达到了95%(含HCN)/98.33%(去HCN)和100%,48 h时含HCN与除去HCN两种苦杏仁精油对粘虫的触杀致死中浓分别为5.10和4.69 μL/mL;苦杏仁精油对粘虫的化蛹期以及羽化期提前1～3 d,并有一定数量的畸形蛹出现,部分试虫虽能正常化蛹并羽化,但其蛹以及成虫虫体均较对照小,且羽化后蛾体萎缩,活动力降低,因展翅困难而死.可见,两种苦杏仁精油对粘虫具有很强的触杀活性,且去HCN的苦杏仁精油对粘虫的活性高于含HCN的苦杏仁精油,其对粘虫生长发育抑制活性主要表现化蛹期以及羽化期提前,苦杏仁精油有望发展为植物性杀虫剂.     

Collophora hispanica,a New Pathogen and Potential Threat to the Almond Industry in Iran

Trunk diseases are potential threats for almond productivity and longevity worldwide, including Iran. In a recent survey on fungal species associated with trunk diseases of almonds in north‐western Iran, Collophora isolates (tentatively identified as Collophora hispanica) were recovered with high frequency from wood samples with internal necrosis and brown to black vascular streaking of almond trees showing symptoms of decline. However, the pathogenic potential of Collophora isolates on almond trees in Iran remains unproven. In this study, the identity of the isolates was further confirmed as C. hispanica based on a combination of morphological data and sequence data of ITS‐rDNA region, and pathogenicity of C. hispanica isolates on almond was evaluated using excised shoot method and in greenhouse experiments. Collophora hispanica isolates induced lesions statistically different from the control, in both excised shoot method and greenhouse assays. Significant differences were observed among the isolates in the length of the lesion induced on wood. Collophora hispanica should be considered as the main trunk pathogens of almond trees in north‐western region of Iran. The distribution and host range of this new pathogen on almond remains to be studied.     

Interaction of almond cystatin with pesticides: Structural and functional analysis

Pesticides are chemical substances that eliminate or control a variety of agricultural pests that damage crops and livestock. They not only affect the targeted pests but also affect the nontargeted systems, raising more concerns for their effect on both plant and animal systems. Cystatins (cysteine protease inhibitor) are ubiquitously present in all living cells and show a variety of important physiological functions. The present study shows the effect of different pesticides (pendimethalin, methoxyfenozide, and Cu^II hydroxide) on purified almond cystatin. Almond cystatin showed concentration‐dependent loss in papain inhibitory activity on interaction with the pesticides, showing maximum loss in the presence of Cu(II) hydroxide and minimum in the case of methoxyfenozide. Native polyacrylamide gel electrophoresis showed maximum degradation of purified cystatin in the presence of Cu(II) hydroxide with insignificant effect in the presence of methoxyfenozide. Structural alterations were significant in the case of Cu(II) hydroxide and less in the case of methoxyfenozide as revealed by UV and fluorescence spectral studies. Secondary structural alterations were further conformed by circular dichroism and Fourier transform infrared spectroscopy. The α‐helix content of almond cystatin decreases from 35.64% (native) to 34.83%, 30.79%, and 29.62% for methoxyfenozide‐, pendimethalin‐, and Cu(II) hydroxide–treated cystatin, respectively. A Fourier transform infrared study shows an amide I band shift for almond cystatin from 1649.15 ± 0.5 to 1646.48 ± 0.6, 1640.44 ± 0.6, and 1635.11 ± 0.3 cm⁻¹ for methoxyfenozide, pendimethalin, and Cu(II) hydroxide, respectively. Values obtained for different thermodynamic parameters (ΔH ⁰, ΔG ⁰, N , and ΔS ⁰) by isothermal titration calorimetric experiments reveal maximum binding of almond cystatin with Cu(II) hydroxide followed by pendimethalin and little interaction with methoxyfenozide.     

新疆小白杏在护手霜中的应用

目的:将新疆南疆地区栽种的主要经济作物之一小白杏应用于化妆品领域,发挥其保持皮肤弹性、柔软和透明的功效。方法:以小白杏杏仁油为原料,运用正交实验设计,加入一定量的乳化剂,通过改变乳化温度、时间、转速,使油相与水相搅拌均匀。结果:最佳配方为:杏仁油13%,羊毛脂4%,蜂蜡3%,尿素3%,乳化剂1.5%,温度85℃,时间7 min,转速140 r/min。结论:以新疆小白杏杏仁油为主要原料,可研制适合于干性皮肤的防皲裂护手霜。     

苦杏仁精油的熏蒸杀虫活性研究

采用三角瓶密闭熏蒸法测定了苦杏仁精油对家蝇、白纹伊蚊、粘虫以及玉米象的熏蒸杀虫活性,结果显示:苦杏仁精油对各试虫均有较强的熏蒸杀虫活性,其中含HCN的精油对家蝇、白纹伊蚊、粘虫以及玉米象的LC50分别为3.09、0.63、4.63、12.03μL/L;除去HCN的精油对家蝇、白纹伊蚊、粘虫以及玉米象的LC50分别为3.53、0.52、4.08、23.46μL/L;熏蒸的时间效应试验结果表明,含有HCN的苦杏仁精油和不含HCN的苦杏仁精油对供试试虫的熏杀速度均较快,其中白纹伊蚊的反应最快,其次为家蝇、粘虫、玉米象.除玉米象外苦杏仁精油中所含的微量HCN对试虫的熏蒸活性影响不大,且2种处理的精油对同种试虫的致死中时差别范围不超过10 min.实验结果表明,苦杏仁精油可作为新型的杀虫活性物质,为苦杏仁精油作为植物源杀虫剂提供了依据.     

Differentiation and Classification of Phytoplasmas Associated with Almond and GF‐677 Witches'‐Broom Diseases using rRNA and rp Genes

Stone fruits are affected by several diseases associated with plant pathogenic phytoplasmas. Previous studies have been shown that phytoplasma agents of almond and GF‐677 witches'‐broom (AlmWB and GWB, respectively) diseases belong to pigeon pea witches'‐broom (16SrIX) phytoplasma group. In this study, partial biological and molecular characterization was used to compare and classify phytoplasma agents of Khafr AlmWB (KAlmWB) and Estahban GWB (EGWB) diseases. Production of different symptoms in periwinkle indicated that agents of KAlmWB and EGWB are differentiable. Expected fragments were amplified from diseased almond and GF‐677 trees in direct PCR using phytoplasma universal primer pairs P1/P7 and rpF1/rpR1 and nested PCR using P1/P7 followed by R16F2n/ R16R2 primer pair. 16S‐rDNA Restriction fragment length polymorphism (RFLP) as well as phylogenetic analysis of rplV‐rpsC and 16S–23S rRNA spacer region sequences classified KAlmWB and EGWB phytoplasmas within 16SrIX‐C (rpIX‐C) and 16SrIX‐B (rpIX‐B) subgroups, respectively.     

扁桃幼果发育的形态解剖学研究

以普通扁桃品种‘纸皮’为研究对象,观察测定了扁桃幼果生长发育动态,并采用石蜡切片法研究了扁桃幼果发育过程。结果表明,扁桃幼果鲜重、体积及果径增长均呈单“S”曲线。大体可分为3个生长时期,增长速率为:第Ⅱ期>第I期>第Ⅲ期。扁桃果实由单心皮上位子房发育而成,边缘胎座,横生胚珠。果皮由外果皮、中果皮和内果皮构成:外果皮是一种复合结构,由表皮毛和表皮细胞组成;中果皮主要是由薄壁细胞和分布其中的维管束组成;内果皮也有丰富的维管束组织分布,其木质化顺序由外向内。中果皮细胞分裂终止早于内果皮。     

Transglycosylation Catalyzed by Almond β-glucosidase and Cloned Pichia etchellsii β-glucosidase II using Glycosylasparagine Mimetics as Novel Acceptors

The stability of almond β-glucosidase in five different organic media was evaluated. After 1 hour of incubation at 30°C, the enzyme retained 95, 91, 81, 74 and 56% relative activity in aqueous solutions [30% (v/v)] of dioxane, DMSO, DMF, acetone and acetonitrile, respectively. Transglucosylation involving p-nitrophenyl β-D-glucopyranoside as donor and β-1-N-acetamido-D-glucopyranose, which is a glycosylasparagine mimic, as acceptor was explored under different reaction conditions using almond βglucosidase and cloned Pichia etchellsii β-glucosidase II. The yield of disaccharides obtained in both reactions turned out to be 3%. Both enzymes catalyzed the formation of (1→3)- as well as (1→6)- regioisomeric disaccharides, the former being the major product in cloned β-glucosidase II reaction while the latter predominated in the almond enzyme catalyzed reaction. Use of β-1-N-acetamido-D-mannopyranose and β-1-N-acetamido-2-acetamido-2-deoxy-D-glucopyranose as acceptors in almond β-glucosidase catalyzed reactions, however, did not afford any disaccharide products revealing the high acceptor specificity of this enzyme.