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Paeonia ludlowii(Stern & G.Taylor) D.Y.Hong, a rare and endangered species, is indigenous to Tibet, China and propagated only by seed. Its natural reproduction is constrained by low fecundity. Excess seed abortion is a key factor restricting its natural reproduction, cultivation, introduction, and protection. In this study, we examined the characteristics of aborted ovules, developmental differences after flowering of normal and aborted ovules, and their ratios at different positions inP. ludlowiiovary. During pollination, fertilisation, and seed development, ovule abortion was frequent, with a random abortion position. There were four types of abortion, namely, abnormal pistil, sterile ovules, abnormal embryo sac, embryo and endosperm abortions. Of these, embryo and endosperm abortions could be divided into early abortion, middle abortion, and late abortion. The early aborted ovules stopped growing on day 12, the endoblast and endosperm in the embryo sac aborted gradually. Furthermore, the shape of the embryo sac cavity changed. The volume of aborted ovules was significantly different from that of fertile ovules. At ripening, the external morphology of different types of aborted seeds was significantly different.Summary statementElucidation of the origin and characteristics of ovule abortion in an endangered Chinese plant species,Paeonia ludlowii.

A new multi-lattice indexing method based on the principle of whole-pattern matching given cell dimensions and space-group symmetry is presented for macromolecular crystallography. The proposed method, termed the multi-crystal data processing suite (MCDPS), features a local correction for prior information accompanied by iterative refinement of experimental parameters, both of which are numerically and experimentally demonstrated to be critical for accurately identifying multiple crystal lattices. Further analysis of data reduction and structure determination with conventional single-crystal programs reveals that the processed multi-lattice data sets are comparable in quality to typical single-crystal ones in terms of crystallographic metrics. Importantly, it is confirmed that careful exclusion of overlapping reflections prior to scaling is necessary to guarantee an accurate data reduction result. The potential for multi-lattice indexing in solving the general macroscopic twinning problem is also explored.

This article mainly describes the chemical and crystal structure of attapulgite as its unique crystal structure possess special physicochemical properties such as large specific surface area, adsorption performance, and cation exchangeability. By modification of attapulgite, such as purification, high temperature roasting and other physical modification or acid–base salt modification, organic modification, surfactant modification and other chemical modification can further improve its physicochemical properties. In this article, the modification methods of two aspects of physical modification and chemical modification are summarized, at the same time, the research progress and achievements of many scholars in attapulgite modification are reviewed. Through modified attapulgite the number of pores increased, channel become loose, pore diameter increases, pore volume increases, interlayer spacing increases, specific surface area increases, chargeability and adsorption activity change, and the adsorption performance of attapulgite is greatly improved. Many scholars have applied modified attapulgite to the treatment of radionuclides, and achieved remarkable results. It has been found that modified attapulgite has U(VI), Eu(III), Cs(III), Th(IV), both Eu(III) and Sr(II) have good adsorption properties, and the adsorption rate and adsorption capacity are greatly improved compared with the original soil. Based on the Summary of the attapulgite modification method and its application in the treatment of radionuclide, some suggestions on the research and application of attapulgite modification and the possible key research directions in the future are further proposed.