Rainbow Haze

The clawing is nitrogen toxicity or possibly due to nutrient salt build from not watering to run off each time... The yellowing is perfectly normal for this late stage of flowering and mainly due to the plant recycling nutrients from the older leaves to use for flower growth.........(this is why defoliation should be avoided, without those leaves the plant would not have a ready made source of pre-made growth elements (amino acids, sugars, carbs etc) available for use in flower formation).