宜昌红荷芋球茎切块繁殖技术研究

以叶用栽培的宜昌红荷芋头球茎为材料,进行了不同球茎大小繁殖系数、球茎切块防腐烂处理、不同切块大小发芽和田间长势比较试验。结果表明,用草木灰或高锰酸钾处理可将球茎切块腐烂率控制在1.3%以下,不同大小切块繁殖出的水芋植株长势没有显著差异。     

不同种植模式魔芋种芋经济效益比较

通过开展3种魔芋种芋的不同种植模式比较试验,探讨魔芋种芋产量及经济效益的关系。试验结果表明,林下间作模式植株健壮,产量最高,单位投入居中,产值最高,投产比最高。露地种植模式,随着密度增加,单芋质量和膨大系数呈下降的趋势,单位投入增大,单产增加,投产比差异缩小。相近密度的林下模式单芋质量和膨大系数相对较大,林下间作模式的魔芋种芋经济效益为最佳。     

宜昌红荷芋球茎切块繁殖技术研究

以叶用栽培的宜昌红荷芋头球茎为材料,进行了不同球茎大小繁殖系数、球茎切块防腐烂处理、不同切块大小发芽和田间长势比较试验.结果表明,用草木灰或高锰酸钾处理可将球茎切块腐烂率控制在1.3%以下,不同大小切块繁殖出的水芋植株长势没有显著差异.     

不同海拔魔芋专用肥应用试验研究

对不同海拔不同魔芋专用肥施用量对魔芋产量和发病率的影响进行试验研究,结果表明,随着海拔升高,发病率降低,海拔700m以上区域较适宜魔芋生长。施用魔芋专用肥的各处理鲜芋产量和膨大系数均高于不施肥（CK）,其中667m2施肥75kg为最佳施肥量,产量和膨大系数较高,发病率较低。播种种芋大小与出苗率呈正相关、与膨大系数呈负相关。     

叶面肥对西红花种球产量及性状的影响

为研究叶面肥对西红花种球生长和产量的影响,通过对西红花喷施4种不同叶面肥,比较不同处理对西红花叶片生长情况、植株死亡率、收获后新生球的大小、产量、上架前球茎烂球情况等。结果表明:喷施DA-6对西红花叶片数和叶片长、收获球茎产量、新生球大小、上架前种球大中球总重和单球重、烂球率等指标均有促进作用。     

11个魔芋品种在汉中地区的种植比较试验

比较了11个不同魔芋品种在汉中地区的种植表现,从品种的抗性、膨大系数、产量等方面进行统计分析。试验结果表明,本地花魔芋H和本地花魔芋L,与对照富源花魔芋在植株生长势、抗性、产量及综合表现上相当,可作为主栽品种推广;白魔芋抗病性强,可作为育种亲本加以利用。     

魔芋杂交新品种‘鄂魔芋1号’

‘鄂魔芋1号’是以花魔芋为母本,白魔芋为父本,经远缘杂交选育而成的新品种。平均产量26.77 t · hm-2,平均繁殖系数13.7。三龄鲜球茎干物质含量16.60%,葡甘聚糖含量55.85%。抗软腐病、灰霉病和干腐病,易感白绢病。从出苗到成熟生育期146 d。适宜湖北省西部山区海拔800 ~ 1 300 m区域种植。     

荸荠球茎的形成与膨大

荸荠的匍匐茎是陆续发生的，其数目也不断增加，在杭州气候条件下，大约到９月中、下旬基本不再增加。匍匐茎发生后，便开始伸长生长，接着以横向膨大生长为主。 球茎大量形成时间在９月中、下旬，以后各时期也有新球茎形成。单个球茎从开始膨大到停止膨大约经历７０天，其中生长最快的时间为球茎开始膨大后２０天左右和４０～７０天，其间经历一个体积和重量增加的“快－慢－快”过程。 荸荠植株生长过程中干物质的分配情况是：球茎形成前主要分配给叶状茎和根系；球茎开始形成至淀粉快速积累期，主要分配给叶状茎和球茎；淀粉快速积累期后，主要分配到球茎中．在所有器官中，叶状茎中干物质的分配率为最高。     

不同类型魔芋种芋的生长分析

通过对不同类型魔芋脱毒种芋的萌芽出苗特性、田间长势、分苗数、田间发病情况、产量、球茎膨大倍数、繁殖系数、生长周期等进行研究.研究结果表明,一级包衣种、二级种、三级种比原原种提前8～18天出苗;一级包衣种、二级种的分苗数较多;一级包衣种、二级种、三级种的田间发病率低于原原种,其中一级包衣种发病率最低,仅为7.4%.二级种、三级种综合性状较好.生产力水平高,膨大倍数高,可通过规模化生产得到大量种芋,解决生产中种芋缺乏的问题.     

不同类型魔芋种芋的生长分析

通过对不同类型魔芋脱毒种芋的萌芽出苗特性、田间长势、分苗数、田间发病情况、产量、球茎膨大倍数、繁殖系数、生长周期等进行研究。研究结果表明，一级包衣种、二级种、三级种比原原种提前8～18天出苗；一级包衣种、二级种的分苗数较多；一级包衣种、二级种、三级种的田间发病率低于原原种，其中一级包衣种发病率最低，仅为7.4％。二级种、三级种综合性状较好，生产力水平高，膨大倍数高，可通过规模化生产得到大量种芋，解决生产中种芋缺乏的问题。     

施用强根素对蓝莓生长及品质的影响

试验以辽宁省果树科学研究所大棚栽培的5年生‘北陆’蓝莓等为材料,研究强根素对蓝莓生长、产量和品质的影响。结果显示,强根素处理对蓝莓树体生长、产量提高和品质改善有促进作用。萌芽至现蕾期、果实膨大至转色期和果实采后施用3次的效果最好,其次为萌芽至现蕾期和果实膨大至转色期施用2次的,施用浓度为15 000倍液。     

不同硒处理对单生朝天椒果实硒含量及品质的影响

开展不同硒处理对单生朝天椒果实硒含量及品质影响的试验。试验结果表明,叶面喷施净硒含量在0~0.985 9 mg/株时,单生朝天椒果实有机硒含量随外源硒使用量增加而增加,但果实有机硒转化率却随外源硒使用量的增加先升后降;单生朝天椒果实有机硒转化率最大时,其喷净硒含量在0.985 9~1.274 1 mg/株。综合考虑施硒量、果实含硒量、有机硒转化率、VC、蛋白质、辣椒素、二氢辣椒素以及膳食适宜供给量等,处理Ⅳ(喷净硒含量0.985 9 mg/株)效果最佳。     

Identification of S-alleles in pear (Pyrus communis L.) cv. ‘Rocha’ and other European cultivars

In this work we report the cloning and identification of S-RNase alleles responsible for gametophytic self-incompatibility (GSI) of ‘Rocha’ pear and of 13 other European pear cultivars that might be used as its pollinators. Partial sequences of S-RNase alleles were amplified by PCR with specific primers hybridising in conserved regions of previously identified S-RNase alleles of Pyrus communis, cloned and sequenced and the S-genotype of eight pear cultivars was fully determined. Three cultivars (‘General Léclerc’ (SqSl), ‘Tosca’ (SbSl) and ‘Alexandrine Douillard’ (SbSk)) shared no S-alleles with ‘Rocha’ (SaSe) and shall be totally compatible with this cultivar. None of the cultivars analysed showed an identical amplification pattern to the one observed in ‘Rocha’, so the other cultivars shall be at least semi-compatible. One new allele was identified in P. communis cv. ‘Beurré d’Avril’ (designated as St). The determination of both S-RNase alleles of cvs ‘Rocha’, ‘Beurré Precoce Morettini’ (SeSk) and ‘Tosca’ and the identification of one S-RNase allele in cvs ‘Carapinheira’ (Sb), ‘Amêndoa’ (Se), ‘Pérola’ (Sk) and ‘Beurré d’Avril’ (St) are important contributions for the effort recently developed worldwide to establish groups of sexual compatibility among European pears.     

Does root-sourced ABA play a role for regulation of stomata under drought in quinoa (Chenopodium quinoa Willd.)

The Andean seed crop quinoa (Chenopodium quinoa Willd.) is traditionally grown under drought and other adverse conditions that constrain crop production in the Andes, and it is regarded as having considerable tolerance to soil drying. The objective of this research was to study how chemical and hydraulic signalling from the root system controlled gas exchange in a drying soil in quinoa. It was observed that during soil drying, relative g_s and photosynthesis A_max (drought stressed/fully watered plants) equalled 1, until the fraction of transpirable soil water (FTSW) decreased to 0.82 ± 0.152 and 0.33 ± 0.061, respectively, at bud formation, indicating that photosynthesis was maintained after stomata closure. The relationship between relative g_s and relative A_max at bud formation was represented by a logarithmic function (r² = 0.79), which resulted in a photosynthetic water use efficiency WUE_Amax_/gs$\text{WU}{\text{E}}_{A_{\text{max}}/g_{\text{s}}}$ of 1 when FTSW > 0.8, and increased by 50% with soil drying to FTSW 0.7–0.4. Mild soil drying slightly increased ABA in the xylem. It is concluded that during soil drying, quinoa plants have a sensitive stomatal closure, by which the plants are able to maintain leaf water potential (ψ_l) and A_max, resulting in an increase of WUE. Root originated ABA plays a role in stomata performance during soil drying. ABA regulation seems to be one of the mechanisms utilised by quinoa when facing drought inducing decrease of turgor of stomata guard cells.     

Changes in fox squirrel anti-predator behaviors across the urban–rural gradient

Predator stimuli created by humans in the urban environment may alter animals’ anti-predator behaviors. I hypothesized that habituation would cause anti-predator behaviors to decrease in urban settings in response to humans. Additionally, I hypothesized that populations habituated to humans would show reduced responses to other predator stimuli. I observed three populations of squirrels (urban, suburban and rural) responses to human approaches, red-tailed hawk vocalizations (Buteo jamaicensis) and coyote (Canis latrans) vocalizations. Mahalanobis distances of anti-predator behaviors in response to human approaches were consistent with the urban–rural gradient. Flight initiation distances (X ² = 26.33, df = 2, P < 0.001) and amount of time dedicated to anti-predator behavior (X ² = 10.94, df = 2, P = 0.004) in response to human approaches were also consistent with the urban–rural gradient. Supporting the habituation hypothesis, naive juvenile squirrels increased flight initiation distances (X ² = 35.89, df = 1, P < 0.001) and time dedicated to anti-predator behaviors (X ² = 9.46, df = 1, P = 0.002) relative to adult squirrels in the same urban environment. Time dedicated to anti-predator behaviors differed among all three sites in response to both coyote (X ² = 9.83, df = 2, P = 0.007) and hawk (X ² = 6.50, df = 2, P = 0.035) vocalizations. Responses to both vocalizations on rural sites (coyote = 45%, hawk = 55%) greater than twice that found on the urban sites (coyote = 11%, hawk = 20%). This is possibly the first case of a transfer of habituation demonstrated under field conditions.     

Tree performance and fruit yield and quality of ‘Okitsu’ Satsuma mandarin grafted on 12 rootstocks

The citriculture in Brazil, as well as in other important regions in the world, is based on very few mandarin cultivars. This fact leads to a short harvest period and higher prices for off-season fruit. The ‘Okitsu’ Satsuma (Citrus unshiu Marc.) is among the earliest ripening mandarin cultivars, and it is considered to be tolerant to citrus canker (Xanthomonas citri subsp. citri Schaad et al.) and to citrus variegated chlorosis (Xylella fastidiosa Wells et al.). Despite having regular fruit quality under hot climate conditions, the early fruit maturation and absence of seeds of ‘Okitsu’ fruits are well suited for the local market in the summer (December through March), when the availability of citrus fruits for fresh consumption is limited. Yet, only a few studies have been conducted in Brazil on rootstocks for ‘Okitsu’. Consequently, a field trial was carried out in Bebedouro, São Paulo State, to evaluate the horticultural performance of ‘Okitsu’ Satsuma mandarin budded onto 12 rootstocks: the citrandarin ‘Changsha’ mandarin (Citrus reticulata Blanco) × Poncirus trifoliata ‘English Small’; the hybrid Rangpur lime (Citrus limonia Osbeck) × ‘Swingle’ citrumelo (P. trifoliata (L.) Raf. × Citrus paradisi Macfad.); the trifoliates (P. trifoliata (L.) Raf.) ‘Rubidoux’, ‘FCAV’ and ‘Flying Dragon’ (P. trifoliata var. monstrosa); the mandarins ‘Sun Chu Sha Kat’ (C. reticulata Blanco) and ‘Sunki’ (Citrus sunki (Hayata) Hort. ex. Tanaka); the Rangpur limes (C. limonia Osbeck) ‘Cravo Limeira’ and ‘Cravo FCAV’; ‘Carrizo’ citrange (Citrus sinensis × P. trifoliata), ‘Swingle’ citrumelo (P. trifoliata × C. paradisi), and ‘Orlando’ tangelo (C. paradisi × Citrus tangerina cv. ‘Dancy’). The experimental grove was planted in 2001, using a 6 m × 3 m spacing, in a randomized block design. No supplementary irrigation was applied. Fruit yield, canopy volume, and fruit quality were assessed for each rootstock. A cluster multivariate analysis identified three different rootstock pairs with similar effects on plant growth, yield and fruit quality of ‘Okitsu’ mandarin. The ‘Flying Dragon’ trifoliate had a unique effect over the ‘Okitsu’ trees performance, inducing lower canopy volume and higher yield efficiency and fruit quality, and might be suitable for high-density plantings. The ‘Cravo Limeira’ and ‘Cravo FCAV’ Rangpur limes induced early-ripening of fruits, with low fruit quality. ‘Sun Chu Sha Kat’ and ‘Sunki’ mandarins and the ‘Orlando’ tangelo conferred lower yield efficiency and less content of soluble solids for the latter rootstock.     

Plant growth,yield, and fruit quality of ‘Fallglo’ and ‘Sunburst’ mandarins on four rootstocks

Vegetative growth, yield, and fruit quality of ‘Fallglo’ and ‘Sunburst’ mandarins on ‘Rangpur’ lime, ‘Swingle’ citrumelo, ‘Orlando’ tangelo, and ‘Cleopatra’ mandarin were evaluated under subtropical climate of Northern São Paulo State, Brazil, from 2000 through 2006 harvest seasons. ‘Fallglo’ mandarin trees had the highest cumulative yield on ‘Rangpur’ lime, and the smallest on ‘Swingle’ citrumelo and ‘Orlando’ tangelo. Plants of this cultivar had the highest yield efficiency on ‘Rangpur’ lime, and the lowest on ‘Orlando’ tangelo. ‘Sunburst’ mandarin trees began to bear fruits later than ‘Fallglo’ mandarin trees, with no differences in yield induced by the rootstocks. ‘Cleopatra’ mandarin induced the most vigorous growth in ‘Fallglo’ mandarin as compared to plants on ‘Swingle’ citrumelo. On the other hand, the largest trees of ‘Sunburst’ mandarin were registered on ‘Orlando’ tangelo, and the smallest on ‘Rangpur’ lime. ‘Sunburst’ mandarin had higher alternate bearing than ‘Fallglo’ regardless the rootstock. Fruit weight and juice content were not affected by the rootstock. These two mandarin scion cultivars may be considered adequate alternatives to produce good fruit quality for the fresh fruit market. ‘Cleopatra’ mandarin and ‘Rangpur lime are suitable rootstocks for ‘Fallglo’ mandarin, whereas all rootstocks evaluated are adequate for ‘Sunburst’ mandarin.     

Horticultural performance of ‘Folha Murcha’ sweet orange onto twelve rootstocks

Despite its outstanding position, the Brazilian citriculture is established on a very limited pool of varieties that limits its expansion and restricts the fruit availability throughout the year. This situation determines the urgent necessity of developing alternative scion and rootstock cultivars, with good performance under local conditions. ‘Folha Murcha’ sweet orange (Citrus sinensis (L.) Osbeck) is a late-harvest cultivar, suitable both for the juice processing industry and the fresh fruit market, being described as tolerant to citrus canker (Xanthomonas citri subsp. citri Schaad et al.), and less affected by citrus variegated chlorosis (Xylella fastidiosa Wells et al.). A study was conducted in Bebedouro, São Paulo State, Brazil, to evaluate the horticultural performance of ‘Folha Murcha’ sweet orange budded onto 12 rootstocks: the citrandarin ‘Changsha’ mandarin (Citrus reticulata Blanco) × Poncirus trifoliata ‘English Small’; the hybrid ‘Rangpur’ lime (Citrus limonia Osbeck) × ‘Swingle’ citrumelo (P. trifoliata (L.) Raf. × Citrus paradisi Macfad.); the trifoliates (P. trifoliata (L.) Raf.) ‘Rubidoux’, ‘FCAV’, and ‘Flying Dragon’ (P. trifoliata var. monstrosa); the ‘Sun Chu Sha Kat’ mandarin (C. reticulata Blanco); the ‘Sunki’ mandarin (Citrus sunki (Hayata) Hort. ex. Tanaka); the ‘Rangpur’ limes (C. limonia Osbeck) ‘Cravo Limeira’ and ‘Cravo FCAV’; ‘Carrizo’ citrange (C. sinensis × P. trifoliata), ‘Swingle’ citrumelo (P. trifoliata × C. paradisi), and ‘Orlando’ tangelo (C. paradisi × Citrus tangerina cv. ‘Dancy’). The experimental grove was planted in 2001, using a 7 m × 4 m spacing, in a randomized block design, with five replications and two plants per plot. No supplementary irrigation was applied. Fruit yield, canopy volume, tree tolerance to drought and to citrus variegated chlorosis, and fruit quality were assessed for each rootstock. Trees grafted onto the ‘Flying Dragon’ trifoliate were smaller in size, but had largest yield efficiency when compared to those grafted onto other rootstocks. Lower alternate bearing index was observed on trees budded onto ‘Cravo FCAV’ ‘Rangpur’ lime. Both ‘Rangpur’ lime rootstocks and the ‘Sunki’ mandarin induced higher tree tolerance to drought. The ‘Flying Dragon’ trifoliate induced better fruit quality and higher tolerance to citrus variegated chlorosis (CVC) to ‘Folha Murcha’ trees. A cluster multivariate analysis identified three groups of rootstocks with similar effects on ‘Folha Murcha’ tree performance. Among the 12 evaluated rootstocks, the ‘Flying Dragon’ trifoliate has a unique effect on plant growth, tolerance to drought and CVC, fruit yield and fruit quality of ‘Folha Murcha’ trees, and may be better suited for high-density plantings.     

Analysis and modeling of gas exchange processes in Scaevola aemula

Scaevola aemula is a popular ornamental crop cultivated as a bedding plant or for hanging baskets. We characterized gas exchange properties of S. aemula ‘New Wonder’ in response to photosynthetically active radiation (PAR), carbon dioxide concentration, and leaf temperature. Net CO₂ assimilation rate (A) was responsive to CO₂, exhibiting a saturation when intercellular CO₂ concentration (C_i) was greater than 600 μmol mol⁻¹. Net CO₂ assimilation rate and dark respiration rate (R_d) were 23.1 and 2.3 μmol m⁻² s⁻¹, respectively, at 25 °C and PAR = 1500 μmol m⁻² s⁻¹. Net CO₂ assimilation rates were similar at leaf temperatures between 20 and 30 °C but significantly reduced at 15 °C. These gas exchange results were used to test the extendibility of a coupled gas exchange model previously developed for cut-roses. Utilizing the gas exchange data measured at 25 °C leaf temperature, several model parameters were independently determined for S. aemula. Model predictions were then compared with observations at different leaf temperatures. The model predicted the rates of net CO₂ assimilation and transpiration of S. aemula reasonably well. Without additional calibration, the model was capable of predicting the temperature dependence of net CO₂ assimilation and transpiration rates. Applying the model to predict the effects of supplemental lighting and CO₂ enrichment on canopy photosynthesis and transpiration rates, we show that this model could be a useful tool for examining environmental control options for S. aemula production in the greenhouse.     

Production protocol development for greenhouse cut Linaria, Lupinus, and Papaver flowers

Linaria maroccana Hook. f. Ann., ‘Lace Violet’, Lupinus hartwegii ssp. cruikshankii Lindl. ‘Sunrise’ and Papaver nudicaule L. ‘Meadow Pastels’ seeds were directly sown into 105 cell plug trays and received either ambient light or supplemental high intensity discharge (HID) lighting. For each species, a 2 × 3 × 3 factorial was used with two light intensities during propagation, three transplant stages, and three night temperatures. Seedlings were transplanted at the appearance of 2–3, 5–6, or 8–9 true leaves. Transplanted Linaria and Papaver seedlings were placed at 5/11, 10/16, or 15/21 ± 1 °C night/day temperatures and Lupinus seedlings were placed at 15/24, 18/25, or 20/26 ± 2 °C night/day temperatures. For this study, the optimum production temperature for Linaria was 10/16 °C as the cut stems produced at 15/21 °C were unmarketable and production time was excessively long at 5/11 °C. At 10/16 °C, Linaria seedlings should be transplanted at the 2–3 leaf stage to maximize stem number, stem length and profitability. For Lupinus the optimum temperature was 15/24 °C due to long stems and high profitability per plant. Lupinus seedlings should be transplanted at the 2–3 leaf stage when grown at 15/24 °C to obtain the longest and thickest stems; however, $/m² week was higher for plants transplanted at the 8–9 leaf stage due to less time in finishing production space. For Papaver, the 15/21 °C temperature was optimal as that temperature produced the longest stems in the shortest duration, resulting in the highest $/m² week. At 15/21 °C Papaver plants should be transplanted at the 2–3 leaf stage. Supplemental HID lighting had no effect on any of the species.