A new DNA marker for sex identification in purple asparagus

Garden asparagus (Asparagus officinalis L.) is an economically-important perennial crop. This plant is dioecious, as there are both male and female individuals; male individuals are preferred over females for agricultural production. To reduce the time required for garden asparagus breeding, various male-specific DNA markers are utilized. Male-specific DNA markers, such as Asp1-T7sp and MSSTS710, are currently available for sex identification in many asparagus cultivars. In the current study, we found that these markers are not suitable for sex identification in the purple asparagus cultivar ‘Pacific Purple’, as male-specific amplification of this marker was detected in some male individuals of this cultivar but not in other males. The Asp1-T7sp marker is suitable for use in sex identification in various Asparagus species related to A. officinalis, indicating that the region around this marker is conserved among these species. Thus, we isolated a DNA fragment around this marker by inverse PCR and produced a new DNA marker, MspHd, based on this sequence. However, like Asp1-T7sp and MSSTS710, MspHd was not suitable for sex identification in the cultivar ‘Pacific Purple’. Since all ‘Pacific Purple’ males have morphologically similar male flowers with functional stamens, we produced a new male-specific marker based on the sex determination gene, MSE1/AspMYB35/AspTDF1, which is responsible for stamen development. This marker, named AspMSD, is suitable for sex identification in ‘Pacific Purple’. In addition, this marker can be utilized for sex identification in various asparagus cultivars and some related Asparagus species.     

Ovarian and retroperitoneal teratomas in a dog

A 2-year-old female Labrador retriever was presented with anorexia and abdominal distention. Laparotomy revealed the presence of a 31-cm ovoid mass in the portion of the left ovary and an 11-cm round mass in the left retroperitoneal region. Both masses were surgically removed. Histopathological examination of the masses revealed a mixture of tissues characteristic of teratomas, such as multiple bronchial and intestinal cysts, hair follicles, sebaceous and apocrine sweat glands, and neuron tissue with intervening cartilage, bone and fat tissue. This paper appears to be the first report of primary retroperitoneal teratoma in the dog.     

鲤鱼鱼鳞胶原蛋白ASC与PSC的比较

以鲤鱼鱼鳞为原料,研究了酸法和酶法提取的鱼鳞胶原蛋白ASC和PSC的异同.经过SDS-凝胶电泳和氨基酸分析可以看出,2种蛋白在分子构型、氨基酸组成等方面的差异并不明显,经过蛋白酶K有限酶解后的图谱证明了这一点.但从差热分析,以及蛋白质受热的分解变化来看,二者之间在热稳定性方面存在一定的差异.推测差距产生的原因与蛋白质制备过程中,胃蛋白酶的作用有关,胶原蛋白两端的非螺旋区域受到酶的作用而分解,非螺旋区域对三螺旋的稳定性起着重要作用,非螺旋区域的分解大大降低了PSC对热的耐受性.     

Carbon-nitrogen interaction related to P,K, Ca,and Mg nutrients in field crops

Carbon (dry matter)-nitrogen relationship was expressed as DM_t = DM₀ × exp(CNI × N_t) in Gramineae crops (including root crops), and DM_t = DM₀ + CNF × N_t in Leguminosae crops, where DM_t is the amount of dry matter at various growth stages, N_t is the amount of nitrogen absorbed at various growth stages, DM₀ is the initial value, and CNI and CNI′ are coefficients. Thus, since the carbon-nitrogen relationship was different between Gramineae and Leguminosae crops, it is expected that the accumulation processes of other minerals such as phosphorus (P), potassium (K), calcium (Ca), or magnesium (Mg) during growth would be different between Gramineae and Leguminosae crops if these nutrients are closely related to the carbon and nitrogen metabolism. As nitrogen is the most important nutrient for plant growth, the relationship between N_t and the amount of other minerals such as phosphorus (P_t), potassium (K_t), calcium (Ca_t), or magnesium (Mg_t) absorbed in plants at various growth stages was examined in field crops.

In Gramineae crops, the P_t-N_t, K_t-N_t, and Mg_t-N_t relationships during growth were described as follows:

where P₀ and Mg₀ are initial values, and PNI, KNI, K_max, and MgNI are coefficients. Since the P_t-N_t and K_t-N_t relationships changed according to the growing conditions, the values of PNI and KNI were statistically estimated from the data of various growth stages at each treatment. As PNI showed a linear regression with CNI, P_t and also K_t was expressed by the equation which included CNI. Thus both phosphorus and potassium accumulation were closely related to the carbon-nitrogen interaction. While the Mg_t-N_t relationship was less affected by various growing conditions, MgNI was estimated from the data including all treatments, indicating that Mg accumulation was regulated only by nitrogen nutrient. Ca_t was not related to N_t.

In Leguminosae crops, the P_t-N_t, K_t-N_t, and Mg_t-N_t relationships were described as follows:

where P_0, K₀, and Mg₀ are initial values, and PNI′ and KNI′ are coefficients. Since the P_t-N_t, K_t-N_t, and Mg_t-N_t relationships were less affected by various growing conditions as in the case of DM_t-N_t, the values of PNI′ and KNI′, and MgNI were estimated from the data including all treatments. Thus, P, K, and Mg accumulation was closely regulated by N nutrient. Ca_t was not related to N_t.

Consequently, in Gramineae crops, P and K accumulation was assumed to be related to the carbon-nitrogen interaction, while in Leguminosae crops, P and K accumulation was assumed to be related to only nitrogen nutrient, indicating that the role of P and K nutrients differed according to differences in the balance of the carbon-nitrogen metabolism. Since MgNI was estimated from the same form of Mg_t-N_t regression regardless of Gramineae and Leguminosae crops, Mg accumulation was assumed to be closely regulated by only nitrogen nutrient. Ca accumulation was neither related to N nutrient nor carbon-nitrogen interaction.     

Increase in Cation Adsorption Induced by Surface Complexation of Sulfate on Andisols and Prediction by “Four-Plane Model”

Abstract

The “Four-plane model” is one of the surface complexation models developed for analyzing the electrostatic charge of synthetic oxides. This model which was applied to the B horizon of Andisols, was equilibrated with an electrolyte solution containing KCl, KNO₃, K₂SO₄ in the concentration range of 0.0033, 0.01, 0.033, 0.1 M, and pH range of 2 to 11. The amounts of NO₃ ^-, Cl^-, SO₄ ^2-, and K⁺ adsorbed were determined from the products remaining in the liquid phase. The increase in the pH value results in the increase of K⁺ adsorption, and decrease of anion adsorption. The increase in the equilibrium concentration increased both K⁺ and anion adsorption. The parameters of the model were determined by measurements and the iterative method. The model have a good agreement between calculated and measured values of cation and anion adsorption. Among the anion species, the amount of adsorbed anions was in the order of SO₄ ^2-?Cl^->NO₃ ^-. The differences in the degree of adsorption were mainly associated with the differences in the equilibrium constants of surface complexation. The surface complexation of the anions produced a negative charge and increased cation adsorption. The degree of surface complexation was most significant in the K₂SO₄ solution, and the phenomenon was considered to be important not only for anion adsorption but also for cation adsorption on Andisols.     

Application of “Four-Plane Model” to the Adsorption of K+, NO3 -, and SO4 2- from a Mixed Solution of KNO3 and K2SO4 on Andisols

To evaluate the interaction between anionic species when they were adsorbed on variable charge soils, we measured the adsorption of NO₃ ^- and SO₄ ^2- on. an Andisol equilibrated with a mixture of KNO₃ and K₂SO₄ solutions. The amount of NO₃ ^- adsorption declined with the increase in the concentration of SO₄ ^2-. On the other hand, the amount of SO₄ ^2- adsorption increased with the increase in the concentration of NO₃ ^-. These phenomena can not be explained by the simple “exchange theory” or the “Three-plane model” unless surface complexation is associated with the changes in the electrical potential of the surface. Therefore, in order to explain the phenomena by using the “Four-plane model” with surface complexation, a new equation was derived for the Diffuse Double Layer (DDL) charge from the “main equation of DDL theory” (equation of electrical potential in DDL) instead of the “Gouy-Chapman equation,” which can be used only for single symmetric electrolytes but nor for a mixture. By introducing the new equation to the computer program for analyzing the Four-plane model, the interaction between anionic species adsorbed on Andisols could be explained well. It was considered that SO₄ ^2- acted as a regulator for the ionic concentration, osmotic pressure and pH of the soil solution, and consequently, these factors affected the vertical distribution and mobility of anionic species and also the mobility of counter-ions in Andisols.     

Studies on soils of Peaty paddy fields I

Rice is the main crop grown in Japan, approximately three million hectares or half of the total arable land being planted to rice. However, not less than 20 percent of the rice fields is estimated of so called “Akiochi” type, which means autumn-decline in English. It has been observed that these low productive paddy soils may be divided roughly into two types, one of which is the soil of well-drained, so called “degraded” paddy field, and the other is the soil of ill-drained one with too much organic matter, humus, in the soil.