为了实现高产优质、环境成本低的双重目标，缓释肥作为新型肥料取代传统氮肥被广泛应用于莲藕栽培。然而，优化的缓释肥施用量如何改善莲藕品质的机制尚不清楚。本研究旨在研究6个缓释肥水平（CK、S1、S2、S3、S4、S5）下对莲藕的光合特性和淀粉合成、积累和理化性质的影响。与CK（0 kg∙ha^-1 SRF）相比，缓释肥处理下莲藕叶片的Pn和SPAD值保持较高水平。进一步研究表明，缓释肥提高了莲藕产量、直链淀粉、支链淀粉、总淀粉含量和淀粉粒数量。在6个缓释肥水平中，S3（1035 kg∙ha^-1 SRF）与CK相比差异最大，并保持在最高水平。随着缓释肥水平的升高，峰值、热浆和最终粘度先降低，后增加，但消减值和糊化温度升高。为了在分子水平上解释这一变化，我们分析了淀粉积累相关酶的活性和淀粉积累相关酶基因的相对表达量，结果表明缓释肥处理下均增加，特别是S3处理下增加最多。总体来说，缓释肥，特别是S3（1035kg∙ha^-1 SRF）作为莲藕种植的适宜肥料比，可以通过影响淀粉积累相关酶和基因来提高莲藕品质。这些结果将有助于低环境成本的优质莲藕的生产。

Phosphomannose isomerase (PMI) encoding gene manA is a desirable selective marker in transgenic research. Understanding of its expression patterns in transgenic plant and establishing highly sensitive detection method based on immunoassay have great impacts on the application of PMI. In this study, PMI-specific monoclonal antibodies were generated using recombinant protein as immunogen, and could be used in Western blot to detect as little as 0.5 ng His-tagged PMI protein or rice expressed PMI protein in sample accounted for 0.4% of single rice grain (about 0.08 mg). PMI protein driven by CaMV-35S promoter was detected in dozens of tested tissues, including root, stem, leaf, panicle, and seed at all developmental stages during rice growing, and PMI protein accounted for about 0.036% of total protein in the leaves at seedling stage. The established method potentially can be used to monitor PMI protein in rice grains.

Propamocarb is an agricultural chemical that has been widely used to protect cucumber plants from downy mildew. To understand the mechanisms of cucumber defense responses to propamocarb, we investigated the physiological and proteomic responses of the cucumber line D0351 with propamocarb application. We found that after treatment with propamocarb, the activities of detoxifying enzymes (glutathione reductase, GR; glutathione S-tramsferase, GST) and soluble sugar content of cucumber fruit were significantly increased, but malonaldehyde (MDA) content was significantly reduced. To identify components of propamocarb responsive signaling, we compared the high resolution two-dimensional gel electrophoresis (2-DE) protein profiles of control and propamocarb-treated fruits, and identified 18 differentially expressed (13 up-regulated and 5 down-regulated) proteins induced by propamocarb which were determined by matrix-assisted laser desorption/ionization timeof- flight mass spectrometry (MALDI-TOF-MS). The majority of the proteins had functions related to detoxication, energy and transport, protein biosynthesis, regulating reactions and defending against stresses. A real-time quantitative reverse transcriptional-polymerase chain reaction (qRT-PCR) was used to compare transcript and protein accumulation patterns for 18 candidate proteins, and the expression of 14 was consistent at both transcript and protein levels. The responses of cucumber proteome to propamocarb seemed complex; the identified proteins may play an important role in regulating adaptation activities following exposure to propamocarb. Data presented herein may shed light on understanding cucumber fruit defense responses under propamocarb treatment.