Efficacy of bacterial antagonists and different commercial products against Fusarium wilt on rocket

Seven experimental trials were carried out to evaluate the efficacy of the bacterial strains Achromobacter xylosoxydans AM1 and Serratia sp. DM1 obtained from suppressive soils and from soilless used rockwool substrates (Pseudomonas putida FC6B, Pseudomonas sp. FC7B, Pseudomonas putida FC8B, Pseudomonas sp. FC9B and Pseudomonas sp. FC24B) against Fusarium wilt on rocket caused by Fusarium oxysporum ff. spp. raphani and conglutinans. Along with these strains, two commercial bioproducts (RootShield—Trichoderma harzianum T22; Cedomon—Pseudomonas chlororaphis MA342) were also tested. Different application strategies such as soil treatment (trials I to VI; 10⁷ and 10⁸ CFU ml⁻¹) and root dipping (trial VII; 10⁸ and 10⁹ CFU ml⁻¹) were performed in a glasshouse in order to test the efficacy of the bacterial strains against Fusarium oxysporum ff. spp. raphani and conglutinans. The lowest disease incidence (16.7%) was observed with the application of Achromobacter sp. AM1, Serratia sp. DM1 at 10⁸ CFU ml⁻¹ and Pseudomonas sp. FC9B at 10⁷ CFU ml⁻¹ against F. oxysporum f. sp. conglutinans (experiment I). Maximum plant biomass (5.0 g/plant) was registered in Serratia sp. DM1 at 10⁸ CFU ml⁻¹ treated plants in trial IV. The trials against F. oxysporum f. sp. raphani (experiment II) showed that the application of Pseudomonas sp. FC7B, P. putida FC8B at 10⁸ CFU ml⁻¹ and P. chlororaphis MA342 at 7.5 × 10⁶ CFU ml⁻¹ significantly reduced disease incidence to values ranging between 87% and 92%. The highest plant biomass was recorded with the application of Achromobacter sp. AM1 and P. putida FC6B at 10⁷ CFU ml⁻¹ (3.9 to 4.2 g) carried out 7 days before the artificial inoculation of the pathogens (trial IV). The present study showed the potential biocontrol activity of the bacterial strains Achromobacter sp. AM1, Serratia sp. DM1 and Pseudomonas sp. FC9B against F. oxysporum f. sp. conglutinans and of Pseudomonas sp. FC7B, P. putida FC8B, P. chlororaphis MA342, Achromobacter sp. AM1 and P. putida FC6B against F. oxysporum f. sp. raphani. Growth-promoting activity of biocontrol bacteria used during the trials was observed.     

网纹甜瓜无土栽培生长动态观察

以土壤栽培为对照,观察了网纹甜瓜无土栽培条件下植株生长,果实膨大的变化.结果表明:无土栽培4月20日、5月5日株高、叶片数均显著高于对照,5月5日之前增加速度是对照的1.26倍、1.36倍,是5月20日至6月19日增加速度的10.9倍、8.9倍.无土栽培授粉后20、30、40 d果实纵径均显著高于对照,授粉前20 d纵径的增加速度是对照的1.29倍,而且前20 d果实纵、横径增加速度是后20 d的5.5倍和3.7倍.     

香蕉无土育苗基质筛选及营养液配方优化

以“巴西”香蕉试管苗为材料,采用单因素随机区组试验设计和正交试验设计方法筛选香蕉无土育苗移栽基质、优化营养液配方,结果表明：（1）珍珠岩是较优的无土移栽基质,移栽50 d后,香蕉袋装苗株高33.84?.25 cm,茎高13.13?.42 cm,茎粗8.61?.37 mm,叶数6.65?.22片,根冠比0.2041?.0125,达到出圃二级苗标准,其次是混合基质。（2）组合KNO3 950 mg/L NH4NO3 412 mg/L CaCl2 332 mg/L KH2PO4 340 mg/L是较有利于香蕉试管苗无土育苗的营养液配方,在此处理下,移栽40 d后,香蕉袋装苗株高27.01?.30 cm,茎高12.83?.62 cm,茎粗9.70?.20 mm,叶数6.49?.07片,根冠比0.2856?.0068,达到出圃一级苗标准。     

苜蓿绿芽无土栽培基质筛选试验

为了选出适宜苜蓿绿芽无土栽培的基质,经过8种基质的对比试验,得出海绵和水培两种处理最优,其中以水培最为省工省时,经济实用。     

有机固体废弃物再生环保型无土栽培基质研究进展

简述了国内外环保型无土栽培基质研究历史和趋势,综述了我国有机固体废弃物再生环保型无土栽培基质在蔬菜生产、观赏植物栽培和城市绿化方面的研究、开发和应用现状.对我国利用有机固体废弃物生产环保型无土栽培基质存在的问题进行了讨论,并对其发展前景进行了展望.     

不同营养液及基质对黄瓜产量和品质的影响

以无土栽培方式探讨了2种营养液及3种基质对黄瓜生育、产量和品质的影响。结果显示：在黄瓜生物学性状、养分吸收、叶绿素含量及瓜条品质等方面国产营养液均优于荷兰营养液，平均增产27％，施肥成本下降50％左右；有机生态基质栽培方法在产量和品质上表现最优，增产30％－35％，成本低廉，栽培方法简便易行，可大面积应用于优质无公害蔬菜生产。     

彩椒有机生态型无土栽培基质的筛选

以彩椒为试材,炉渣、蛭石、菇渣、锯末和稻壳等为栽培基质材料,腐熟棉籽饼和消毒鸡粪代替营养液,进行有机生态型无土栽培试验。采用类旋转排列试验设计方法,分析比较8种基质配方与两种有机肥料配方组合对彩椒生长及防病增产的影响,并设土壤栽培为对照。结果表明,彩椒无土栽培基质以炉渣:菇渣(1:3)+(5kg腐熟棉籽饼+5kg消毒鸡粪)/m3为最佳;其次为炉渣:菇渣:锯末:稻壳(2:6:1:1)+(5kg腐熟棉籽饼+5kg消毒鸡粪)/m3。     

便携式无土栽培基质多参数无线检测仪

为实现无土栽培基质参数的快速准确测量,基于自制的基质多参数复合传感器,并结合Zig Bee无线网络技术,研制了便携式基质多参数无线检测仪。检测仪采用分体式设计,由无线复合传感器和手持终端两部分组成。无线复合传感器采集基质参数信息,并以无线的方式将信息发送到手持终端;手持终端对接收到的测量参数信息进行处理分析、显示、存储和查询等。检测仪性能试验表明,含水率测量误差为-0.4%~3.1%,相对误差为-3.2%~9.6%,且对不同基质具有较好的适应性;电导率测量误差为-0.015~0.179 m S/cm,相对误差为-4.7%~10%,且对不同基质具有较好的适应性;温度测量误差为-0.63~0.69℃,相对误差为-1.1%~3.3%。检测仪能够满足无土栽培基质参数检测的要求。     

不同营养液对无土栽培黄瓜生长发育的影响及其经济效益分析

本试验研究了农用化肥代替化学试剂,做无土栽培营养液肥源的可行性。试验结果表明,利用普通化肥代替化学试剂配制营养液,不仅是可行的,而且能大幅度降低成本,经济效益显著。在春夏季试验中,适当增加营养液中氨态氮化肥的比例,明显地促进黄瓜早熟,提高早期产量。在秋冬季试验中,适当比例的氨态氮肥,能促进黄瓜总产量的提高。春秋两次试验还表明,若含硝态和酰胺态氮的化肥同时作氮源时,可不同程度地促进黄瓜的营养生长及生殖生长。此外本试验还研究了不同营养液对黄瓜叶片中叶绿素的含量,氨基酸的含量及光合作用的影响。     

Oxyfertigation of a greenhouse tomato crop grown on rockwool slabs and irrigated with treated wastewater: Oxygen content dynamics and crop response

This work assesses the seasonal dynamics of the substrate oxygen content and the response to nutrient solution oxygen enrichment (oxyfertigation) of an autumn-spring tomato crop grown on rockwool slabs and irrigated with treated wastewater of very low dissolved oxygen (DO) content under Mediterranean greenhouse conditions. DO values in the nutrient solution were clearly higher for the oxygen-enriched (14.6 mg L⁻¹) tomato crop than for the non-enriched one (4.5 mg L⁻¹). However, DO values in the substrate solution were similar for both oxygen treatments (mean seasonal values of 5.1 and 4.8 mg L⁻¹ for the enriched and the non-enriched one, respectively), except for a short crop period at the end of the cycle when they were significantly higher for the oxygen-enriched crop. For both treatments, substrate DO values were highest for the winter period and decreased progressively during the spring period, reaching minimum values of around or below 3 mg L⁻¹ at the end of the spring. The oxygen enrichment of the nutrient solution did not affect any of the irrigation and fertigation parameters evaluated in the tomato crop: water uptake, volumetric water content of the substrate, electrical conductivity (EC) or nutrient concentration in the leached nutrient solution. Moreover, the oxygen enrichment of the nutrient solution did not affect the aboveground biomass and the biomass partitioning, the fresh weight of total and marketable tomato fruits or the tomato fruit quality parameters. Overall, it appears that oxygen deficiency conditions did not occur as the substrate DO values were higher than, or about, 3 mg L⁻¹ throughout most of the tomato crop cycle for both treatments and the rockwool slabs maintained good aeration conditions throughout the whole cycle.